TWI503709B - Liquid crystal display device with touch panel - Google Patents

Description

Liquid crystal display device with touch panel

The present invention relates to a liquid crystal display device with a touch panel used in a mobile phone or a tablet computer, and more particularly to a fly-scatter function having a crack relative to a glass substrate, and does not generate a touch panel module and A liquid crystal display device with a touch panel that is detached from a bonding portion between liquid crystal display panels.

In recent years, with the high functionality and diversification of various electronic devices such as mobile phones, portable terminals, and personal computers, the touch panel has been actively used as one of the input means for using such electronic devices. There are various methods for the touch panel, and a touch panel having a light-transmitting property and being attached to the front surface of the liquid crystal display panel of the electronic device via the adhesive layer is a capacitive touch panel module.

In the past, the surface of the information display portion of the portable terminal device has gradually used a plastic plate having high light transmittance from the viewpoint of easily viewing the displayed information or being easily damaged even if it is dropped. However, the portable terminal device is required to be thinner and lighter, and the strength may be insufficient when the plastic plate is thinned. In order to solve this problem, the surface of the information display department, in recent years A tempered glass substrate is gradually used.

However, when only the reinforced glass substrate is used, when the portable terminal device is dropped, there is a problem that the glass substrate is broken and the glass substrate is scattered. Therefore, a surface which is attached to the surface of the tempered glass substrate to prevent scattering of the glass scattering film is used. In general, a polyethylene terephthalate (PET) film which is inexpensive and has a scattering preventing effect is used as a glass scattering preventing film. The PET film generally has a low adhesion to the adhesive layer, and in order to improve the tightness, a PET film provided with an adhesive layer called a film of an easy-adhesive layer is used.

In addition, the PET film may have interference patterns due to the refractive index. In order to improve the situation, it has been studied to bond the cellulose acetate film with an adhesive layer to the outermost surface of the glass substrate as a protective film. A method of preventing scattering of the glass substrate (for example, refer to Patent Document 1).

On the other hand, the capacitive touch panel module is formed on a transparent substrate, and has an X-electrode pattern formed by a transparent conductive film extending in the X direction and composed of other transparent conductive films. A Y electrode pattern extending in the Y direction. Touching the surface of the touch panel with a finger to contact the X electrode pattern and the Y electrode pattern, and detecting the electrostatic capacitance change at the position by the X and Y electrode patterns.

The capacitive touch panel module having the double transparent conductive film and the touch surface being a glass surface has a transparent optical double-sided tape (OCA) or a filler, and another glass substrate It is laminated to a two-layer transparent conductive film.

However, in order to require further weight reduction and empty battery capacity It is ensured that the capacitive touch panel module disclosed in Patent Document 2 is provided with a two-layer transparent conductive film in a direction orthogonal to each other, and the glass substrate is used as a touch surface, but only one piece of the glass substrate is used. . Therefore, it is aimed at achieving a thinner overall.

However, when a thin capacitive touch panel having only one glass substrate disclosed in Patent Document 2 is bonded to a liquid crystal display panel via an adhesive layer or the like, moisture contained in the entire touch panel is not easily discharged. Peeling occurs at the bonding portion of the adhesive layer, and there is a problem that the visibility is deteriorated or the panel is warped.

[Previous Technical Literature] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open Publication No. 2011-209512

[Patent Document 2] Japanese Patent Laid-Open Publication No. 2011-186717

The present invention has been made in view of the above problems and circumstances, and an object of the present invention is to provide a scattering prevention function for glass rupture with respect to a glass substrate, and to release or capture the entire liquid crystal display device with a touch panel. A liquid crystal display device with a touch panel that does not cause the peeling of the bonding portion between the touch panel module and the liquid crystal display panel or the warpage of the panel.

The inventors of the present invention have studied the above-mentioned problems in order to solve the above problems. During the discussion, it was found that the above-mentioned touch panel module has a cellulose ester film having a specific thickness on the transparent conductive film, and the foregoing When the liquid crystal display panel has a cellulose ester film on the outermost surface, and the cellulose ester film of the touch panel module and the cellulose ester film of the liquid crystal display panel are bonded to each other via an adhesive layer, the cellulose can be formed by cellulose The excellent moisture permeability of the ester film releases or traps the moisture of the entire module, and can be a liquid crystal with a touch panel that does not cause peeling of the bonding portion of the adhesive layer due to moisture or warpage of the panel. The display device thus completes the present invention.

That is, the above problems of the present invention can be solved by the following means.

A liquid crystal display device with a touch panel, comprising a touch panel module and a liquid crystal display device with a touch panel of the liquid crystal display panel, wherein: (1) the touch panel module has a square a transparent conductive film formed on the outermost glass substrate, and having a cellulose ester film A having a thickness in the range of 15 to 60 μm on the transparent conductive film, (2) the liquid crystal display panel having fibers on the outermost surface The ester film B, the cellulose ester film A and the cellulose ester film B are bonded to each other via the adhesive layer C.

2. The liquid crystal display device with a touch panel according to Item 1, wherein the thickness of the cellulose ester film B is in the range of 10 to 40 μm.

3. The liquid crystal display device with a touch panel according to item 1 or 2, wherein the cellulose ester film A is in contact with one side of the liquid crystal display panel It has a hard coat layer containing an acrylic resin.

4. The liquid crystal display device with a touch panel according to Item 1, wherein the cellulose ester film A is a cellulose diacetate having an ethylenic group substitution degree in the range of 2.0 to 2.5.

5. The liquid crystal display device with a touch panel according to Item 1, wherein the in-plane phase difference value Ro of the cellulose ester film A is in an environment of a temperature of 23 ° C and a relative humidity of 55% RH at a light wavelength of 590 nm. When measured, it is in the range of 0 to 100 nm.

6. The liquid crystal display device with a touch panel according to Item 1, wherein the in-plane phase difference value Ro of the cellulose ester film A is in an environment of a temperature of 23 ° C and a relative humidity of 55% RH at a light wavelength of 590 nm. In the measurement, it is in the range of 105 to 160 nm, and the direction of the slow axis of the cellulose ester film A is 45°±10° or 135°±10° with respect to the absorption axis of the polarizing plate. The cellulose ester film A was tilted and attached.

According to the above-described means of the present invention, it is possible to provide a scattering prevention function with respect to the crack of the glass substrate, and to release or trap the moisture contained in the entire interior of the liquid crystal display device with the touch panel without generating touch. A liquid crystal display device with a touch panel attached to the peeling of the bonding portion between the panel module and the liquid crystal display panel or the warpage of the panel.

Although the development mechanism and mechanism of action of the effects of the present invention are still unclear, they are presumed as follows.

A liquid crystal display device with a touch panel according to the present invention is characterized in that A liquid crystal display device having two cellulose ester films therein, wherein the touch panel module has a cellulose ester film A having a thickness in the range of 15 to 60 μm, and the liquid crystal display panel also has a cellulose ester film B. Since the cellulose ester has a hydroxyl group, the cellulose ester film has excellent moisture permeability which can be trapped and released moisture. Therefore, compared with other types of resin films other than cellulose ester, by using a cellulose ester film, moisture can be released or trapped, and the adhesion of the touch panel module to the liquid crystal display panel can be alleviated. The effect of the layer significantly improves the peeling failure of the bonding portion between the touch panel module and the liquid crystal display panel or the warpage of the panel.

1‧‧‧ glass substrate

2‧‧‧1st electrode pattern

3‧‧‧Insulation

4‧‧‧2nd electrode pattern

5‧‧‧Adhesive layer

6‧‧‧Cellulose ester film A

7‧‧‧hard coating

T‧‧‧Touch Panel Module

8‧‧‧Adhesive layer C

9‧‧‧Cellulose ester film B

10‧‧‧ polarizing film

11‧‧‧Protective film

P‧‧‧Polar plate

12‧‧‧LCD panel

V‧‧‧Liquid Display Department

FIG. 1 is a schematic view of a liquid crystal display device with a touch panel according to the present invention.

The liquid crystal display device with a touch panel of the present invention has a touch panel module and a liquid crystal display device with a touch panel of the liquid crystal display panel, and the following features: (1) the touch panel module has a square a transparent conductive film formed on the outermost glass substrate, and having a cellulose ester film A having a thickness in the range of 15 to 60 μm on the transparent conductive film, (2) the liquid crystal display panel having fibers on the outermost surface The ester film B, the cellulose ester film A and the cellulose ester film B are bonded to each other via the adhesive layer C.

This feature is a technical feature common to the scope of patent application from the first to sixth aspects of the patent application.

The cellulose on the outermost surface of the liquid crystal display panel from the viewpoint of moisture release property and trapping property inside the liquid crystal display device with a touch panel of the present invention, and flexibility, thinning, and weight reduction The thickness of the ester film B is preferably in the range of 10 to 40 μm.

In the present invention, the film thickness of the cellulose ester film A is set to be slightly thick, because it can sufficiently have a scattering prevention function against cracking of the glass substrate, and at the same time, it is more easily released or trapped from contact with the external environment. The moisture that penetrates the side of the touch panel module.

Further, the cellulose ester film A has a hard coat layer containing an acrylic resin, and the affinity with the adhesive contained in the adhesive layer can be improved by the acrylic resin on the surface of the film, and the adhesion can be further improved to further suppress the adhesion portion. It is preferred to peel off.

Further, the cellulose ester film A containing cellulose diacetate having a degree of substitution of ethyl ketone in the range of 2.0 to 2.5 can more easily release or trap water, so it is preferable and can be pulled by Stretching operations and the like to impart a desired phase difference.

Further, the in-plane retardation value Ro of the cellulose ester film A can be raised in the range of 0 to 100 nm in the measurement of the light wavelength of 590 nm in an environment of a temperature of 23 ° C and a relative humidity of 55% RH. It is better to observe the visibility when displaying the naked eye.

Further, when the in-plane phase difference value Ro of the aforementioned cellulose ester film A is in the environment of a temperature of 23 ° C and a relative humidity of 55% RH, at the wavelength of light In the measurement of 590 nm, it is in the range of 105 to 160 nm, and the direction of the slow axis of the cellulose ester film A is 45° ± 10° or 135° ± 10° with respect to the absorption axis of the polarizing plate. In this manner, when the cellulose ester film A is inclined and bonded, it is preferable to improve the visibility when the polarizing sunglasses are worn to observe the display of the display device. This is because the phase difference of the above range is given and the circular polarizing plate is combined with the polarizing plate mounted on the liquid crystal display panel, thereby improving the visibility when the polarized sunglasses are worn.

The invention and its constituent elements, as well as the modes and forms for carrying out the invention, are described in detail below. In the present application, "~" is used in the sense that the numerical values described before and after are used as the lower and upper limits.

<Liquid crystal display device with touch panel>

Hereinafter, an example of the configuration of a liquid crystal display device with a touch panel having cellulose ester films A and B according to the present invention will be described with reference to FIG.

The touch panel module of the present invention comprises: a glass substrate 1 from a surface side; and a first electrode pattern 2 formed on a surface of one of the glass substrates to cover the first electrode pattern a transparent insulating film 3 formed on the surface, a second electrode pattern 4 formed on the insulating film and disposed in a direction orthogonal to the extending direction of the first electrode pattern, and covering the second electrode pattern A pair of transparent conductive films having a square shape of a protective film 3 made of a transparent insulating film formed on the surface as described above is basically configured. The surface of the glass substrate is a touch surface.

The cellulose ester film A6 of the present invention is bonded to the transparent conductive film via the adhesive layer 5 to form the touch panel module T, and is via the present invention. The adhesive layer C8 is bonded to the cellulose ester film B9 on the outermost surface of the liquid crystal display panel 12 to constitute the liquid crystal display portion V. On the liquid crystal display panel, a polarizing plate P is bonded, and the polarizing film 10 is sandwiched by the cellulose ester film B9 and the protective film 11. When the cellulose ester film A is provided with a hard coat layer, the hard coat layer 7 is in contact with the adhesive layer C8.

In other words, the liquid crystal display device with a touch panel of the present invention has a basic structure in which a glass substrate, a transparent conductive film, a cellulose ester film A, an adhesive layer, and a polarizing film having a cellulose ester film B are bonded from the surface side. The board and each layer of the liquid crystal display panel are configured.

First, each element other than the cellulose ester film of the present invention will be described.

(glass substrate)

The glass substrate of the present invention is composed of a sheet of tempered glass, and is not particularly limited as long as it is a glass substrate for a flat panel, and synthetic quartz glass for optics, tempered glass, or the like can be used. In the past, from the viewpoint of weight reduction, polyethylene terephthalate (PET) resin, other engineering plastic resin of polycarbonate (PC) resin, or cyclic olefin system such as norbornene may be used. A sheet of a resin sheet such as a resin has problems in terms of visibility, high-grade feeling, and strength, and the sheet of the tempered glass can be directly peeled off and used.

However, when only the tempered glass substrate is used, when the portable terminal device is dropped, the glass substrate is broken, and the glass substrate is scattered. Therefore, it has been considered to adhere a glass scattering film with an adhesive layer to the surface of the tempered glass substrate to prevent scattering of the glass substrate. For example, can be listed A technique of attaching a polyethylene terephthalate (PET) film which is inexpensive and has a scattering preventing effect, or a cellulose triacetate film disclosed in Patent Document 1, to a surface, but Since the anti-glass scattering film is bonded to the surface of the glass substrate, it is not intended to have the effect of preventing the glass from scattering and the effect of releasing or trapping moisture in the liquid crystal display device with the touch panel.

The thickness of the tempered glass substrate is not particularly limited, but is preferably in the range of 30 to 800 μm, and is preferably in the range of 50 to 600 μm in terms of both strength and weight.

(transparent conductive film)

The transparent conductive film itself is of a capacitive type, and is composed of a first electrode pattern and a second electrode pattern formed on the surface of the substrate, and a transparent insulating film disposed between the electrode patterns. The transparent insulating film is not particularly limited, and for example, SiO ₂ or the like can be used.

The first electrode pattern and the second electrode pattern are made of a transparent conductive material such as ITO (indium tin oxide) or IZO (indium zinc oxide) or a thin metal wire. In particular, ITO can be used from the viewpoint of conductivity and transparency.

The first electrode pattern is formed by arranging, for example, a conductive pattern extending in the longitudinal direction (X direction), and the second electrode pattern is arranged such that a conductive pattern extending in the lateral direction (Y direction) is arranged, for example. A square-shaped conductive film is formed. The conductive film can be formed by forming a mask of an electrode pattern shape on a substrate and forming an electrode pattern by an alkali etching process, or A predetermined laser is irradiated onto the substrate to continuously form a conductive film pattern.

At the end portions of the first electrode pattern and the second electrode pattern, the extraction electrodes not shown are disposed. The user can press the surface conductor of the glass substrate with a finger or a stylus to bring the second electrode pattern into contact with the first electrode pattern on the glass substrate. And the contact is electrically detected through the end of the extraction electrode, thereby detecting the pressed position. In the first electrode pattern of the glass substrate, a dot-shaped spacer can be provided as necessary.

(polarizer)

The polarizing plate using the cellulose ester film B of the present invention has a cellulose ester film B on the surface of the polarizing film prepared by immersing in an iodine solution and stretching on the opposite side to the liquid crystal cell. The cellulose ester film B is preferably bonded to the polarizing film by a water-based adhesive containing a completely saponified polyvinyl alcohol or the like as a main component.

The thickness of the cellulose ester film B is preferably in the range of 10 to 40 μm from the viewpoint of water release property and collection property, and flexibility, thin film formation, and weight reduction.

The polarizing film which is a main component of a polarizing plate is an element which passes only the light of a polarizing surface in a certain direction, and the currently known polarizing film is a polyvinyl alcohol type polarizing film, and although it is iodine or a dichroism. The dye is dyed in a polyvinyl alcohol-based film, but is not limited thereto.

For example, a polarizing film can be used: a polyvinyl alcohol aqueous solution is formed into a film and this is uniaxially stretched and dyed, or uniaxially stretched after dyeing, and then It is preferably a durable treatment with a boron compound. It is preferable to use a polarizing film having a film thickness of 5 to 30 μm, preferably 8 to 15 μm.

The protective film to be bonded to the other surface of the polarizing film is not particularly limited, and is preferably a cellulose triacetate film. Further, a so-called optical compensation film having a phase difference may be used. The difference film) constitutes a polarizing plate which can expand the viewing angle. These can be produced, for example, by the method of JP-A-2002-71957.

A commercially available polarizing plate protective film can be more preferably used, and examples thereof include KC8UX2MW, KC4UX, KC5UX, KC4UY, KC8UY, KC12UR, KC4UEW, KC8UCR-3, KC8UCR-4, KC8UCR-5, KC4FR-1, and KC4FR-2. KC8UE, KC4UE (manufactured by Konica Minolta Advanced Layer Co., Ltd.), etc.

(liquid crystal display panel)

For the liquid crystal display panel, it is preferable to use a reflective type, a transmissive type, a semi-transmissive liquid crystal display device, or a liquid crystal display of various driving methods such as TN type, STN type, OCB type, VA type, IPS type, and ECB type. Device.

(adhesive layer C)

The adhesive for bonding the cellulose ester film A and the cellulose ester film B of the present invention contains a thermosetting resin or an ultraviolet (UV) curable resin or a chemically curable resin, preferably optically transparent. In addition, it can show moderate viscoelastic or adhesive properties.

Specific examples of the adhesive include an acrylic copolymer, an epoxy resin, a polyurethane, a polyoxyalkylene polymer, a polyether, a butyral resin, a polyamide resin, and a polyvinyl alcohol. Adhesives such as resins and synthetic rubbers or adhesives. In the present invention, an adhesive which is formed into a film by a heat curing method, a photo hardening method, a chemical reaction or the like and is hardened is preferable. Among them, an acrylic copolymer or an epoxy resin can be preferably used because it is the easiest to control the adhesiveness, transparency, weather resistance, and durability.

The above adhesive may be of a single liquid type or a type in which two or more liquids are mixed before use. Further, the above-mentioned adhesive may be a solvent system using an organic solvent as a medium, or an emulsion type, a colloidal dispersion type, or an aqueous solution type which is a medium containing water as a main component, or may be a solventless type. The concentration of the above-mentioned adhesive can be appropriately determined depending on the film thickness after adhesion, the coater, the coating conditions, and the like, and is usually in the range of 0.1 to 50% by mass.

The thickness of the adhesive layer of the present invention is preferably in the range of 0.1 to 100 μm, more preferably in the range of 0.5 to 50 μm, and particularly preferably in the range of 0.5 to 30 μm. When the coating is applied, the viscosity of the adhesive at 25 ° C is generally in the range of 1000 to 6000 mPa ‧ sec, preferably in the range of 2000 to 4000 mPa ‧ sec, for example, in the range of 3,000 to 4,000 mPa ‧ sec. Here, the viscosity is, for example, a value obtained by using a B-type viscometer BH II manufactured by Tokimec Co., Ltd., and rotating the rotor for 30 seconds after standing. The Young's modulus (E) of the fully cured adhesive resin is preferably in the range of 1 to 100 MPa, for example, in the range of 5 to 20 MPa.

The storage elastic modulus of the adhesive preferably has a storage elastic modulus at 25 ° C in the range of 1.0 × 10 ⁴ to 1.0 × 10 ⁸ Pa, particularly preferably in the range of 1.5 × 10 ⁵ to 1.0 × 10 ⁷ Pa. When the storage elastic modulus of the adhesive is 1.0 × 10 ⁴ Pa or more, sufficient cutting workability and high pencil hardness can be obtained, and when it is 1.0 × 10 ⁸ Pa or less, sufficient adhesion can be obtained. The storage elastic modulus of the adhesive layer was measured by forming the adhesive layer forming composition on the polyethylene terephthalate support, and peeling it off, and using a dynamic viscoelasticity measuring device (manufactured by Rheometric Co., Ltd.) "ARES") The storage elastic modulus of the adhesive layer at 25 ° C was measured in a heating mode (temperature rising rate 5 ° C / min, frequency 10 Hz).

Examples of the acrylic pressure-sensitive adhesive include a crosslinking agent such as an isocyanate crosslinking agent, an epoxy crosslinking agent, an aziridine crosslinking agent, and a metal chelate crosslinking agent, and (meth) Methyl acrylate, ethyl (meth)acrylate, (meth)acrylic acid ester, isobutyl (meth)acrylate, n-hexyl (meth)acrylate, 2-ethylbutyl (meth)acrylate, One or two or more kinds of alkyl acrylates having 1 to 20 carbon atoms such as 2-ethylhexyl (meth) acrylate, isooctyl (meth) acrylate or decyl (meth) acrylate, and the above acrylic acid Alkyl ester copolymerized (meth)acrylic acid, itaconic acid, maleic acid, maleic anhydride, 2-hydroxyethyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, etc. The copolymer is reacted.

Examples of the epoxy resin adhesive include a resin composition in which an ultraviolet curable epoxy resin is modified by a polyoxyalkylene elastomer, and a precipitated ceria is added as an inorganic filler. For example, Edmund can be used. "NORLAND Optical Adhesive NOA68" manufactured by Optics or "Optical Bomb" by Sony Chemical and Information Device Super View Resin".

In order to promote photohardening of the aforementioned adhesive, it is preferred to further contain a photopolymerization initiator. The blending amount of the photopolymerization initiator is preferably contained in the range of photopolymerization initiator:adhesive=20:100 to 0.01:100 by mass ratio.

Specific examples of the photopolymerization initiator include alkylphenones, acetophenones, diphenylketones, hydroxydiphenylketones, Michelin, α-amyl esters, thioxanthone, and the like. Derivatives, but are not limited thereto. As such a commercially available product, for example, Irgacure 184, Irgacure 907, Irgacure 651 manufactured by BASF Japan Co., Ltd., and the like are exemplified as preferred examples.

In the method of providing the adhesive layer, it is preferable to provide the above-mentioned adhesive-containing composition by coating, and examples thereof include a bar coating method, a knife coating method, a roll coating method, a sheet coating method, and a die-casting mold coating method. A conventionally known method such as a cloth method, a gravure coating method, a curtain coating method, or an inkjet method.

In the case of thermal curing, it is preferred to apply heating at 80 ° C or higher in a dryer, and the heating time can be appropriately set.

The light source for the UV hardening treatment can be used without limitation as long as it is a light source capable of generating ultraviolet rays. For example, a low pressure mercury lamp, a medium pressure mercury lamp, a high pressure mercury lamp, an ultra high pressure mercury lamp, a carbon arc lamp, a metal halide lamp, a xenon lamp, or the like can be used.

The irradiation conditions vary depending on various lamps, and the amount of activation energy rays to be irradiated is usually in the range of 50 to 1000 mJ/cm ² , preferably in the range of 50 to 300 mJ/cm ² . Further, the heat treatment temperature after UV curing is preferably 80 ° C or higher.

In the present invention, after the adhesive layer is provided on the cellulose ester film A of the touch panel module, it is preferred to laminate the release sheet to the surface before bonding to the polarizing plate.

As the release sheet, various release sheets can be used, and the representative one is composed of a base sheet having a peeling property on the surface. The base material sheet may be a film of a polyester resin, a polyethylene resin, a polypropylene resin, a polystyrene resin, a polycarbonate resin, or the like, or a film such as a filler or the like, or a synthetic film or the like. . Further, a paper base material such as cellophane, clay coated paper, or tape paper may be mentioned.

In order to impart releasability to the surface of the base sheet, a release agent such as a thermosetting polyoxyalkylene resin or an ultraviolet curable polydecane resin may be adhered to the surface by coating or the like. The coating amount of the release agent is preferably in the range of 0.03 to 3.0 g/m ² . The sheet is peeled off, and the surface having the release agent is allowed to be laminated by being in contact with the above-mentioned adhesive layer.

<Measurement of water absorption and moisture permeability of film>

The present invention is characterized in that the moisture of the entire module is released or captured by the excellent moisture permeability of the cellulose ester film, thereby realizing a peeling of the bonding portion which does not cause the adhesive layer due to moisture and the panel is not provided. A liquid crystal display device with a touch panel attached to the warp. Therefore, the water absorption and moisture permeability of the film are important, which can be a major factor in the design of the cellulose ester film. The water absorption rate and moisture permeability of the film were measured by the following methods.

The water absorption rate of the film is determined according to JIS K 7209-1984 (water absorption rate of plastic and boiling water absorption test method), and is converted into a thickness of 40 μm. The water absorption rate (%) of the film. The preferred water absorption of the cellulose ester film of the present invention is in the range of 1.5 to 6.0% when measured by the above method. Particularly preferred, the cellulose ester film A is in the range of 4.0 to 6.0%.

Further, the moisture permeability of the film can be measured according to JIS Z0208, and the moisture permeability of the film converted to a thickness of 40 μm can be measured. The preferred moisture permeability of the cellulose ester film of the present invention is in the range of 700 to 2000 g/m ² /24 hr (40 ° C, 90% RH test) when measured by the above method. Particularly preferred, the cellulose ester film A is in the range of 700 to 1500 g/m ² /24 hr.

In the case of a cellulose ester film, the water absorption rate and the moisture permeability can be adjusted by the type of the cellulose ester, the type and content of the additive such as the plasticizer to be used, and the film thickness of the film, among which the cellulose ester The type is dominant.

<Cellulose ester film>

Next, the cellulose ester film A and the cellulose ester film B of the present invention will be described. The item common to the cellulose ester film A and the cellulose ester film B is sometimes referred to simply as a cellulose ester film.

The cellulose ester film A and the cellulose ester film B of the present invention may be different or the same as the cellulose ester resin and other additives, but the thickness of the cellulose ester film A is in the range of 15 to 60 μm. It is necessary for those who exhibit the function of preventing the scattering of glass and releasing or trapping water. When the thickness is less than 15 μm, the glass scattering property and the water release property or the trapping property are weak. When the thickness exceeds 60 μm, the flexibility is deteriorated, and the warpage of the panel is likely to occur, which is not suitable for thinning and light weight. membrane.

The thickness of the cellulose ester film B is preferably in the range of 10 to 40 μm as described above, from the viewpoint of water release property, trapping property, and film formation, and further, it is a cellulose ester. The film A is thinner, and is preferable from the viewpoints of panel warpage, flexibility, and weight reduction.

(cellulose ester resin)

The cellulose ester resin which can be used for the cellulose ester film A and the cellulose ester film B of the present invention is preferably selected from the group consisting of cellulose (di-, tri) acetate, cellulose propionate, cellulose butyrate, At least one of cellulose acetate propionate, cellulose acetate butyrate, cellulose acetate phthalate, and cellulose phthalate.

Among these, particularly preferred cellulose esters include cellulose (di, tri) acetate, cellulose acetate propionate or cellulose acetate butyrate. Among them, the cellulose ester film A of the present invention is preferably cellulose diacetate from the viewpoint of moisture control.

The cellulose triacetate is preferably one having a degree of substitution of ethanethio group in the range of from 2.6 to 2.95, more preferably a cellulose triacetate having a degree of substitution of ethanethio group in the range of from 2.8 to 2.9.

For the cellulose diacetate, it is preferred to use an ethyl thiol group having a degree of substitution in the range of 2.0 to 2.5. Commercially available products include L20, L30, L40, and L50 manufactured by Daicel Co., Ltd., and Ca398-3, Ca398-6, Ca398-10, and Ca398- manufactured by Eastman Chemical Japan Co., Ltd. 30, Ca394-60S and so on. In particular, in the case where the degree of substitution of the oxime group is in the range of 2.2 to 2.45, it is preferable from the viewpoint of high moisture permeability, release of water, release property, and phase difference.

a mixed lower fatty acid ester such as cellulose acetate propionate or cellulose acetate butyrate, having a fluorenyl group having a carbon number of 2 to 4 as a substituent, and having a degree of substitution with an ethyl ketone group of X, a propyl fluorenyl group When the degree of substitution of the butyl group is Y, it is preferred to satisfy the cellulose resins of the following formulas (I) and (II).

Formula (I) 2.6≦X+Y≦3.0

Formula (II) 1.0≦X≦2.5

Among them, cellulose acetate propionate can be used, and among them, it is preferable to satisfy 1.9 ≦ X ≦ 2.5, 0.1 ≦ Y ≦ 0.9. The portion not substituted with the above mercapto group is usually present as a hydroxyl group. These can be synthesized by a generally known method. The method for measuring the degree of substitution of the above thiol group can be measured in accordance with ASTM-D817-96.

Further, the cellulose ester used in the present invention preferably has a number average molecular weight (Mn) of 60,000 or more and less than 180,000, and the ratio Mw/Mn of the weight average molecular weight (Mw) / number average molecular weight (Mn) is located. In the range of 1.5 to 5.5, particularly preferably in the range of 2.0 to 5.0, more preferably in the range of 2.5 to 5.0, and particularly preferably in the range of 3.0 to 5.0.

The number average molecular weight (Mn) and molecular weight distribution (Mw) of the cellulose ester can be measured by high performance liquid chromatography. The measurement conditions are as follows.

Solvent: dichloromethane

Pipe column: Shodex K806, K805, K803G (made by Showa Denko Co., Ltd., connected by three)

Column temperature: 25 ° C

Sample concentration: 0.1% by mass

Detector: RI Model 504 (made by GL Science)

Pump: L6000 (manufactured by Hitachi, Ltd.)

Flow rate: 1.0ml/min

Calibration curve: A calibration curve formed using 13 samples of standard polystyrene STK standard polystyrene (manufactured by Tosoh Corporation) Mw = 1000000 to 500. The 13 samples are preferably used at almost equal intervals.

The raw material cellulose of the cellulose ester used in the present invention may be wood pulp or cotton linters, and the wood pulp may be conifer or broad-leaved tree, but is preferably a conifer. From the viewpoint of the peeling property at the time of film formation, cotton lint is preferably used. The cellulose ester thus produced can be suitably mixed or used alone.

For example, cellulose esters from cotton linters: cellulose esters from wood pulp (coniferous trees): ratios of cellulose esters from wood pulp (broadleaf trees), 100:0:0, 90:10:0, 85: 15:0, 50:50:0, 20:80:0, 10:90:0, 0:100:0, 0:0:100, 80:10:10, 85:0:15, 40:30: 30.

In the present invention, 1 g of the cellulose ester resin is placed in 20 ml of pure water (electrical conductivity: 0.1 μS/cm or less, pH 6.8), and stirred at 25 ° C for 1 hr in a nitrogen atmosphere, preferably, the pH is located. In the range of 6 to 7, the conductivity is in the range of 1 to 100 μS/cm.

(additive)

The cellulose ester film may be used in combination with a plasticizer in order to improve moisture permeability and fluidity of the composition or flexibility of the film. Examples of the plasticizer include a phthalate type, a fatty acid ester type, a trimellitate type, a phosphate type, a polyester type, a sugar ester type, and an acrylic type polymer. Among these, a plasticizer of a polyester type and a sugar ester type polymer can be preferably used from the viewpoint of moisture permeability. The polyester-based plasticizer has better non-movability and extraction resistance than the phthalate-based plasticizer such as dioctyl phthalate.

The plasticizer can be selected or used in accordance with the application, thereby being applicable to a wide range of applications.

The acrylic polymer is preferably a homopolymer or copolymer of acrylic acid or alkyl methacrylate. Examples of the acrylate monomer include methyl acrylate, ethyl acrylate, acrylic acid (iso-n-propyl) acrylate, acrylic acid (normal, iso-, secondary, tertiary) butyl ester, and acrylic acid (positive, different, secondary). Amyl ester, acrylic acid (n- or iso)hexyl ester, acrylic acid (n-, iso)heptyl ester, acrylic acid (n-, iso-) octyl ester, acrylic acid (n-, iso-) decyl ester, acrylic acid (n-, iso) tetradecyl ester, (2-ethylhexyl) acrylate, ε-caprolactone, (2-hydroxyethyl) acrylate, (2-hydroxypropyl) acrylate, (3-hydroxypropyl) acrylate, acrylic acid (4-hydroxybutyl) ester, (2-hydroxybutyl) acrylate, (2-methoxyethyl) acrylate, (2-ethoxyethyl) acrylate, etc., or the above acrylate Change to methacrylate. The acrylic polymer is a homopolymer or a copolymer of the above monomers, but preferably has 30% by mass or more of methyl acrylate alone. The body unit, in addition, preferably has 40% by mass or more of methyl methacrylate monomer unit. Particularly preferred is a homopolymer of methyl acrylate or methyl methacrylate.

A polyester-based plasticizer is a reactant of a monovalent to tetravalent carboxylic acid and a monovalent to hexavalent alcohol, but mainly obtained by reacting a divalent carboxylic acid with an alcohol. Typical examples of the divalent carboxylic acid include glutaric acid, itaconic acid, adipic acid, phthalic acid, sebacic acid, and sebacic acid. Further, the polyester-based plasticizer is preferably an aromatic terminal ester-based plasticizer. An aromatic terminal ester-based plasticizer, preferably an ester compound having a structure in which at least one benzene monocarboxylic acid of phthalic acid, adipic acid, and at least one alkanediol having 2 to 12 carbon atoms are reacted, and finally The compound structure may have an adipic acid residue and a phthalic acid residue, and when the ester compound is produced, it can be reacted as an acid anhydride or an esterified product of a dicarboxylic acid.

a benzene monocarboxylic acid component, for example, benzoic acid, p-tert-butylbenzoic acid, o-methylbenzoic acid, m-methylbenzoic acid, p-methylbenzoic acid, dimethylbenzoic acid, ethylbenzoic acid, n-propyl The benzoic acid, the aminobenzoic acid, the ethoxylated benzoic acid and the like are preferably benzoic acid. Further, these may be used alone or in combination of two or more.

The alkanediol component having 2 to 12 carbon atoms is ethylene glycol, 1,2-propylene glycol, 1,3-propanediol, 1,2-butanediol, 1,3-butanediol, 1,2-propanediol, 2-methyl-1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 2,2-dimethyl-1,3-propanediol (neopentylene glycol), 2, 2 -diethyl-1,3-propanediol (3,3-dihydroxymethylpentane), 2-n-butyl-2-ethyl-1,3-propanediol (3,3-dimethylolbutane) ), 3-methyl-1,5-pentanediol, 1,6-hexanediol, 2,2,4-trimethyl- 1,3-pentanediol, 2-ethyl-1,3-hexanediol, 2-methyl-1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, 1,12-octadecanediol and the like. Among them, particularly preferred is 1,2-propanediol. These diols may be used alone or in a mixture of two or more.

The aromatic terminal ester type plasticizer may be any of the oligoester or polyester type, and the molecular weight is preferably in the range of 100 to 10,000, preferably in the range of 350 to 3,000. Further, the acid value is 1.5 mgKOH/g or less, and the hydroxyl value is 25 mgKOH/g or less. Particularly preferably, the acid value is 0.5 mgKOH/g or less, and the hydroxyl value is 15 mgKOH/g or less.

Specifically, the compounds shown below can be listed, but are not limited thereto.

The sugar ester-based compound is an ester other than the cellulose ester, and is a compound obtained by esterifying all or a part of the OH group of the sugars such as the following monosaccharide, disaccharide, trisaccharide or oligosaccharide, and specific examples thereof include A compound represented by the general formula (1) or the like is given.

(wherein R ₁ to R ₈ represent a hydrogen atom, a substituted or unsubstituted alkylcarbonyl group having 2 to 22 carbon atoms, or a substituted or unsubstituted arylcarbonyl group having 2 to 22 carbon atoms; and R ₁ to R ₈ may be Same or different)

In the following, the compound represented by the general formula (1) is represented by a more specific one (Compound 1-1 to Compound 1-23), but is not limited thereto. In the following table, when the average degree of substitution is less than 8.0, it means that one of R ₁ to R ₈ is a hydrogen atom.

These plasticizers are preferably added in an amount of 0.5 to 30 parts by mass based on 100 parts by mass of the cellulose ester film.

(phase difference adjuster)

For the cellulose ester film, for example, a compound represented by the general formula (I) to (IV) described in JP-A-2003-344655, or a Japanese Patent Laid-Open Publication No. 2005-134884 can be used. A phase difference adjusting agent such as a compound represented by the general formula (IV) and a compound represented by [Chemical Formula 1] to [Chemical Formula 11] described in JP-A-2004-109657. By using such a phase difference adjusting agent, a desired phase difference can be obtained even under relatively gentle stretching conditions, and failure such as breakage can be reduced.

In the present invention, the phase difference adjusting agent is preferably added in the range of 0.1 to 10% by mass, more preferably 0.5 to 5% by mass, more preferably 1 to 5, based on the cellulose ester film. Added within the range of mass %. These may also be used in combination of two or more types.

(Antioxidants)

The cellulose ester film preferably also contains an antioxidant.

A preferred antioxidant is a phosphorus-based or phenol-based system, and a phosphorus-based or phenol-based system is preferably combined.

The antioxidants which can be preferably used in the present invention are explained below.

<Phenolic antioxidants>

In the present invention, a phenolic antioxidant is preferably used, and a hindered phenol compound is particularly preferably used.

Specific examples of the hindered phenol compound include: n-octadecyl 3-(3,5-di-tri-butyl-4-hydroxyphenyl)-propionate, n-octadecyl 3-(3, 5-di-tertiary butyl-4-hydroxyphenyl)-acetate, n-octadecyl 3,5-di-tertiary butyl-4-hydroxybenzyl ester, n-hexyl 3,5-di - Tert-butyl-4-hydroxyphenyl benzyl ester, n-dodecyl 3,5-di-tertiary butyl-4-hydroxyphenyl benzyl ester, neo-dodecyl 3-(3 ,5-di-tertiary butyl-4-hydroxyphenyl)-propionate, dodecyl β(3,5-di-tri-butyl-4-hydroxyphenyl)-propionate, B Α-(4-hydroxy-3,5-di-tertiary butylphenyl)-isobutyrate, octadecyl α-(4-hydroxy-3,5-di-tertiary butylphenyl )-isobutyrate, octadecyl α-(4-hydroxy-3,5-di-tert-butyl-4-hydroxyphenyl)-propionate, 2-(n-octylthio)ethyl -3,5-di-tertiary butyl-4-hydroxy-benzyl ester, 2-(n-octylthio)ethyl-3,5-di-tert-butyl-4-hydroxy-phenylacetic acid Ester, 2-(n-octadecylsulfanyl)ethyl-3,5-di-tert-butyl-4-hydroxyphenylacetate, 2-(n-octadecylsulfanyl)ethyl-3, 5-di-tertiary butyl-4-hydroxy-benzyl Acid ester, 2-(2-hydroxyethylsulfanyl)ethyl-3,5-di-tertiary butyl-4-hydroxybenzyl ester, diethyl diol bis-(3,5-di-third Butyl-4-hydroxy-phenyl)propionate, 2-(n-octadecylthio)ethyl-3-(3,5-di-tertiarybutyl-4-hydroxyphenyl)propionate , stearylamine-N,N-bis-[ethylene 3-(3,5-di-tri-butyl-4-hydroxyphenyl)propionate], n-butylimido-N,N- Bis-[ethylene 3-(3,5-di-tri-butyl-4-hydroxyphenyl)propionate], 2-(2-stearyloxyethylthio)ethyl-3,5- Di-tertiary butyl-4-hydroxybenzyl ester, 2-(2-stearyloxyethylthio)ethyl-7-(3-methyl-5-tributyl-4-hydroxybenzene Heptanoate, 1,2-propanediol bis-[3-(3,5-di-tri-butyl-4-hydroxyphenyl)propionate], ethylene glycol bis-[3-(3, 5-di-tertiary butyl-4-hydroxyphenyl)propionate], neopentyl glycol bis-[3-(3,5-di-tri-butyl-4-hydroxyphenyl)propionate ], ethylene glycol bis-(3,5-di-tertiary butyl-4-hydroxyphenyl acetate), glycerol-1-n-octadecanoate-2,3-bis-(3,5- Di-tertiary butyl-4-hydroxyphenyl acetate), pentaerythritol-tetrakis-[3-(3',5'-di-tertiarybutyl-4'-hydroxyphenyl)propionic acid Ester], 1,1,1-trishydroxymethylethane-tri-[3-(3,5-di- Grade butyl-4-hydroxyphenyl)propionate], sorbitol hexa-[3-(3,5-di-tri-butyl-4-hydroxyphenyl)propionate], 2-hydroxyethyl -7-(3-methyl-5-tert-butyl-4-hydroxyphenyl)propionate, 2-stearyloxyethyl-7-(3-methyl-5-tertiary butyl 4-hydroxyphenyl)heptanoate, 1,6-n-hexanediol-bis[(3',5'-di-tri-butyl-4-hydroxyphenyl)propionate], neopentyl alcohol -Tetra-(3,5-di-tri-butyl-4-hydroxyhydrocinnamate). The hindered phenol compound of the above type is sold, for example, by the company name "Irganox 1076" and "Irganox 1010" by BASF Japan Co., Ltd.

<Phosphorus antioxidants>

As the phosphorus-based antioxidant, a phosphorus-based compound such as a phosphite, a phosphonite, a phosphinite, or a phosphane can be used. As the phosphorus compound, a conventionally known compound can be used. For example, it is preferably JP-A-2002-138188, JP-A-2005-344044, paragraph number 0022~0027, JP-A-2004-182979, paragraph number 0023~0039, Japanese special Kaiping 10-306175, and Japanese special Kaiping 1 -254744, Japanese Patent Laid-Open No. 2-270892, Japanese Patent Laid-Open No. 5-202078, Japanese Patent Laid-Open No. 5-178870, Japanese Special Table 2004-504435, Japanese Special Table 2004-530759, and Japanese Special Purpose 2005- It is described in the specification of 353229.

The amount of the phosphorus-based compound to be added is usually in the range of 0.01 to 10 parts by mass, preferably 0.05 to 5 parts by mass, more preferably 0.1 to 3 parts by mass, per 100 parts by mass of the resin.

Examples of the phosphorus-based compound include triphenylphosphite, diphenylisodecylphosphite, phenyldiisodecylphosphite, and tris(nonylphenyl) in addition to the compound represented by the above general formula. Phosphite, tris(didecylphenyl)phosphite, tris(2,4-di-tert-butylphenyl)phosphite, 10-(3,5-di-tertiary butyl-4 -hydroxybenzyl)-9,10-dihydro-9-oxo-10-phosphinophen-10-oxide, 6-[3-(3-tert-butyl-4-hydroxy-5-methylphenyl) a single subunit of propoxy]-2,4,8,10-tetra-tert-butyldiphenyl[d,f][1.3.2]dioxaphosphorane, tridecylphosphite Phosphate ester compound; 4,4'-tert-butyl-bis(3-methyl-6-tris-butylphenyl-di-tridecylphosphite Diphosphite-based compound such as ester), 4,4'-extended isopropyl-bis(phenyl-di-alkyl (C12-C15) phosphite); triphenylphosphonite, tetra ( 2,4-di-tertiary butylphenyl)[1,1-biphenyl]-4,4'-diylbisphosphinate, tetrakis(2,4-di-tert-butyl-5 a phosphonite compound such as -methylphenyl)[1,1-biphenyl]-4,4'-diylbisphosphonite; triphenylmonoalkoxyphosphine, 2,6 a monoalkoxyphosphine ester compound such as dimethylphenyl diphenyl monoalkoxyphosphine; triphenyl tertiary phosphane, tris(2,6-dimethoxyphenyl)triphosphate A tertiary phosphane compound such as an alkane.

Phosphorus compounds of the above type are, for example, "Sumilizer GP" by Sumitomo Chemical Co., Ltd., "ADK STAB PEP-24G", "ADK STAB PEP-36" and "ADK STAB 3010" by ADEKA Co., Ltd. BASF Japan Co., Ltd. sells under the trade name "IRGAFOS P-EPQ" and "GSY-P101" by Yuki Chemical Industry Co., Ltd.

(other antioxidants)

Further, there may be mentioned di-dodecyl-3,3'-thiodipropionate, di-tetradecyl-3,3'-thiodipropionate, di-octadecyl-3, Sulfur antioxidants such as 3'-thiodipropionate, pentaerythritol tetrakis(3-dodecylthiopropionate), 2-tris-butyl-6-(3-tert-butyl-2 -hydroxy-5-methylbenzyl)-4-methylphenyl acrylate, 2-[1-(2-hydroxy-3,5-di-tri-pentylphenyl)ethyl]-4,6 a heat-resistant processing stabilizer such as di-tertiary amyl phenylpropionate, 3,4-dihydro-2H-1-benzopyran-based compound described in JP-A-08-27508, and 3,3 '-Helical di-dihydrobenzopiperine compound, 1,1- a helical decane compound, a morpholine, a thiomorpholine, a thiomorphomorph, a sulfur dioxide morpholine, a compound having a piperazine skeleton in a partial structure, a dialkoxybenzene compound described in JP-A-03-174150, and the like. Deoxidizer, etc. Part of the structure of such antioxidants may be suspended from a portion of the polymer, or may be suspended from the polymer regularly, or part of the molecular structure of the additive introduced into the plasticizer, acid scavenger, ultraviolet absorber, and the like.

In the present invention, the antioxidant is preferably added in the range of 0.1 to 10% by mass, more preferably 0.5 to 5% by mass, and more preferably 1 to 5% by mass. These can be used in combination of two or more.

(other additives)

The cellulose ester film of the present invention may contain various compounds or the like as an additive in addition to the above compounds in accordance with the purpose.

<Acid capture agent>

The acid scavenger preferably contains an epoxide as an acid scavenger described in the specification of U.S. Patent No. 4,137,201. The epoxides as such acid scavengers contain diglycidyl ethers which are known in the art and are various polyols, especially rings of about 8 to 40 moles per 1 mole of polyol. a metal epoxide such as a diol derived from condensation, a diglycidyl ether of glycerin or the like (for example, in a vinyl chloride polymer composition, and a vinyl chloride polymer composition, which has been conventionally used , epoxidized ether condensation product, diglycidyl ether of bisphenol A (ie 4,4'-dihydroxydiphenyldimethylmethane), epoxidized unsaturated a fatty acid ester (especially an ester of an alkyl group of about 4 to 2 carbon atoms of a fatty acid having 2 to 22 carbon atoms (for example, butyl epoxy stearyl phthalate)), and capable of oxidizing long-chain fatty acids in various epoxidations Epoxidized vegetable oils and other unsaturated natural oils exemplified by triglycerides and the like (for example, epoxidized soybean oil and the like) (sometimes referred to as epoxidized natural glycerides or unsaturated fatty acids, such fatty acids are generally Contains 12 to 22 carbon atoms)).

<light stabilizer>

The light stabilizer may, for example, be a hindered amine light stabilizer (HALS) compound, which is a known compound, for example, as described in columns 3 to 5 of the specification of U.S. Patent No. 4,619,956 and columns 3 to 5 of the specification of No. 4,839,405. It contains 2,2,6,6-tetraalkylpiperidine or a compound, or such an oxygen addition salt or a complex of these with a metal compound. Further, a light stabilizer described in JP-A-2007-63311 can be used.

<UV absorber>

The ultraviolet absorber preferably has an absorption energy of a wavelength of 370 nm or less from the viewpoint of preventing deterioration by ultraviolet rays, and preferably has a small absorption of visible light having a wavelength of 400 nm or more from the viewpoint of liquid crystal display properties. . For example, an oxydiphenyl ketone type compound, a benzotriazole type compound, a salicylate type compound, a diphenyl ketone type compound, a cyano cyanoacrylate type compound, a nickel complex type compound, etc. are mentioned, but it is preferable. A diphenyl ketone compound or a benzotriazole compound having little coloration. In addition, Japanese Patent Laid-Open No. Hei 10-182621, Japanese Patent Application No. 8-337574 The ultraviolet absorber described in the publication, and the polymer ultraviolet absorber described in JP-A-6-148430.

Specific examples of the benzotriazole-based compound include 2-(2'-hydroxy-5'-methylphenyl)benzotriazole and 2-(2'-hydroxy-3',5'-di- Tertiary butylphenyl)benzotriazole, 2-(2'-hydroxy-3'-tertiarybutyl-5'-methylphenyl)benzotriazole, 2-(2'-hydroxy-3 ',5'-di-tertiary butylphenyl)-5-chlorobenzotriazole, 2-(2'-hydroxy-3'-(3",4",5",6"-tetrahydroortene Phthathymidine imine methyl)-5'-methylphenyl)benzotriazole, 2,2-methylenebis(4-(1,1,3,3-tetramethylbutyl)-6 -(2H-benzotriazol-2-yl)phenol), 2-(2'-hydroxy-3'-tertiary butyl-5'-methylphenyl)-5-chlorobenzotriazole, 2 -(2'-hydroxy-3'-tertiarybutyl-5'-(2-octyloxycarbonylethyl)-phenyl)-5-chlorobenzotriazole, 2-(2'-hydroxy-3 '-(1-Methyl-1-phenylethyl)-5'-1,1,3,3-tetramethylbutyl)phenyl)-benzotriazole, 2-(2H-benzotriene Zin-2-yl)-6-(linear and side chain dodecyl)-4-methylphenol, octyl-3-[3-tert-butyl-4-hydroxy-5-(chloro-2H -benzotriazol-2-yl)phenyl]propionate with 2-ethylhexyl-3-[3-tributyl-4-hydroxy-5-(5-chloro-2H-benzotriazole a mixture of -2-yl)phenyl]propionate, etc. However, it is not limited to this.

In addition, commercially available products include TINUVIN 326, TINUVIN 109, TINUVIN 171, TINUVIN 900, TINUVIN 928, TINUVIN 360 (both manufactured by BASF Japan), LA31 (made by Adeka Co., Ltd.), and Sumisorb 250 (manufactured by Sumitomo Chemical Co., Ltd.). RUVA-100 (manufactured by Otsuka Chemical Co., Ltd.).

Specific examples of the diphenylketone compound include 2,4-dihydroxy group Phenyl ketone, 2,2'-dihydroxy-4-methoxydiphenyl ketone, 2-hydroxy-4-methoxy-5-sulfonyldiphenyl ketone, bis(2-methoxy- 4-hydroxy-5-benzimidylphenylmethane) or the like, but is not limited thereto.

In the present invention, the ultraviolet absorber is preferably added in the range of 0.1 to 20% by mass, more preferably 0.5 to 10% by mass, and more preferably 1 to 5% by mass. These can be used in combination of two or more.

<rough agent>

In the cellulose ester film of the present invention, fine particles such as a roughening agent are added, and from the viewpoint of handling property and strength improvement, fine particles of an inorganic compound or fine particles of an organic compound are exemplified. The roughening agent is preferably as fine as possible, and the fine particles may, for example, be cerium oxide, titanium oxide, aluminum oxide, zirconium oxide, calcium carbonate, kaolin, talc, sintered calcium silicate, calcium silicate hydrate, aluminum silicate, magnesium citrate. Inorganic fine particles such as calcium phosphate or crosslinked polymer fine particles. Among them, cerium oxide is preferred because the haze of the resin substrate is low. Since the cerium oxide-like fine particles are surface-treated by an organic substance in many cases, the haze of the resin substrate can be lowered, which is preferable.

The organic substance which can be preferably subjected to surface treatment may, for example, be a halogenated alkane, an alkoxydecane, a decazane or a nonane. The larger the average particle diameter of the fine particles, the larger the sliding effect, and conversely, the smaller the average particle diameter, the better the transparency.

Further, the average particle diameter of the secondary particles of the fine particles is in the range of 0.05 to 1.0 μm. The average particle diameter of the secondary particles of the preferred fine particles is in the range of 5 to 50 nm, more preferably in the range of 7 to 14 nm. These particles In the cellulose ester film, irregularities in the range of 0.01 to 1.0 μm can be formed on the surface of the cellulose ester film, so that it can be preferably used. The content of the fine particles in the cellulose ester film is preferably in the range of 0.005 to 0.3% by mass based on the cellulose ester.

Examples of the fine particles of cerium oxide include AEROSIL 200, 200V, 300, R972, R972V, R974, R202, R812, OX50, TT600, etc. manufactured by Nippon Aerosil Co., Ltd., preferably AEROSIL 200V, R972, R972V, R974, R202, R812. These particles may be used in combination of two or more kinds. When two or more types are used in combination, they can be used in combination by any ratio. At this time, AEROSIL 200V and R972V can be used in a range of 0.1:99.9 to 99.9:0.1 by mass ratio.

The presence of the fine particles in the cellulose ester film as the above-mentioned roughening agent can also be used as another purpose for enhancing the strength of the cellulose ester film.

<Manufacture of cellulose ester film by solution fluid casting method>

A preferred method of producing the cellulose ester film of the present invention will be described. However, it is not limited to this.

(1) Dissolution step

In a dissolving pot, a cellulose ester resin, other additives, and/or a recycled material are added to an organic solvent mainly composed of a cellulose ester resin, and dissolved while stirring. The steps of the coating.

The dissolution of the cellulose ester resin can be carried out by a method which is carried out under normal pressure, a method of performing at a boiling point or lower of the main solvent, or a method of pressurizing at a boiling point or higher of the main solvent, and is disclosed in Japanese Laid-Open Patent Publication No. Hei 9-95544. A method of performing a cooling and dissolving method as described in Japanese Laid-Open Patent Publication No. Hei 9-95557, or a method of performing a high pressure as described in Japanese Laid-Open Patent Publication No. Hei 11-21379 Various methods of dissolving, etc., are particularly preferably carried out by pressurizing at a boiling point or higher of the main solvent.

The recycled material is a thinner material that is pulverized into a thinner film, which is formed at the time of film formation at the time of film formation, or a film material other than the specification due to abrasion or the like. .

(2) Fluid casting film step

This is a coating made by a liquid-feeding pump (for example, a pressurized quantitative gear pump) to be fed to a pressurizing mold, and continuously conveyed to an endless metal conveyor belt, such as a stainless steel belt or a rotating metal drum. The step of casting a coating fluid from the slit of the pressurizing die at a position of the fluid casting film on the metal support.

It is preferable to adjust the slit shape of the nozzle portion of the mold to easily make the film thickness uniform to the press mold. The press mold may be a coat hanger mold or a T mold, and any of them may be preferably used. The surface of the metal support is mirrored. In order to increase the film forming speed, two or more press molds may be provided on the metal support, and the amount of the coating material may be divided and laminated. Alternatively, it is also preferable to obtain a film of a laminated structure by a co-fluid casting method in which a plurality of coating fluids are simultaneously cast.

(3) Solvent evaporation step

This is a step of heating a film (a coating film formed by casting a coating fluid onto a support for a fluid casting film) into a support for a fluid casting film to evaporate the solvent.

When evaporating the solvent, a method of blowing from the side of the diaphragm and/or a method of transferring heat from the inside of the support by a liquid, or a method of transferring heat from the inside by means of radiant heat may be used, due to heat transfer of the liquid inside. The method is preferred because of its high drying efficiency. Further, these methods may be preferably combined to be used. Preferably, the film on the support after the fluid casting is dried on the support in an environment of 40 to 100 ° C. In order to maintain the environment at 40 to 100 ° C, it is preferred to blow the hot air of this temperature onto the diaphragm or by means of infrared rays or the like.

From the viewpoint of surface quality, moisture permeability, and peelability, it is preferred to peel the film from the support in the range of 30 to 120 seconds.

(4) Stripping step

This is a step of peeling off the film after evaporating the solvent on the metal support at the peeling position. The peeled film is sent to the next step.

The temperature in the peeling position on the metal support is preferably in the range of 10 to 40 ° C, more preferably in the range of 11 to 30 ° C.

The amount of residual solvent at the time of peeling off the film on the metal support at the time of peeling is different depending on the strength of the drying conditions, the length of the metal support, and the like, but it is preferably in the range of 50 to 120% by mass. When in the residue When the film is too soft at the time of peeling, when the film is too soft, the flatness at the time of peeling is impaired, and the peeling tension is likely to be uneven or vertical streaks, so that economical speed and quality can be achieved. Determine the amount of residual solvent at the time of peeling.

The residual solvent amount of the membrane is defined by the following formula.

Residual solvent amount (%) = (mass of the film before heat treatment - mass of the film after heat treatment) / (mass of the film after heat treatment) × 100

The heat treatment at the time of measuring the amount of residual solvent is a heat treatment performed at 115 ° C for 1 hour.

The peeling tension when the metal support and the film are peeled off is usually in the range of 196 to 245 N/m. However, when wrinkles are likely to occur at the time of peeling, it is preferable to peel off at a tension of 190 N/m or less, and it is better to be able to In the range of the lowest tension of the peeling ~166.6 N/m, it is preferable to peel off in the range of the lowest tension ~137.2 N/m, and it is particularly preferable to peel in the range of the minimum tension ~100 N/m.

In the present invention, it is preferred that the temperature in the peeling position on the metal support is in the range of -50 to 40 ° C, particularly preferably in the range of 10 to 40 ° C, and preferably in the range of 15 to 30 ° C. Inside.

(5) Drying and stretching steps

After the peeling, the film is conveyed by using a drying device in which a plurality of rolls are alternately passed through a drying device, and/or a tenter stretching device which is conveyed at both ends of the film by a jig, and the film is used. dry.

The drying means is generally a method of blowing hot air to both sides of the diaphragm, but there is also a means of irradiating microwaves for heating to replace the hot air. Excessive rapid drying can easily damage the planarity of the finished film. Drying at a high temperature can be started when the residual solvent is 8% by mass or less. Drying is carried out in the range of approximately 40 to 250 ° C throughout the entire process. The special system is dried in the range of 40 to 160 °C.

When a tenter stretching apparatus is used, it is preferable to use a device which can independently control the holding length of the film (the distance from the start of grip to the grip) by left and right grip means of the tenter. Further, in the tentering step, in order to improve the planarity, it is preferable to produce segments which intentionally have different temperatures.

Further, it is preferable to provide the neutral zone in such a manner that the sections do not interfere with each other in different temperature sections.

The stretching operation can be carried out in multiple stages, and it is preferred to carry out biaxial stretching in the direction of the fluid casting film and the width direction. Further, in the case of biaxial stretching, biaxial stretching or simultaneous biaxial stretching may be performed.

In this case, the so-called stepwise, for example, stretching in different stretching directions may be performed sequentially, or stretching in the same direction may be divided into multiple stages, and stretching in different directions may be added to any stage. That is, for example, the following stretching steps can be performed.

‧ stretching in the direction of the fluid casting film - stretching in the width direction - stretching in the direction of the fluid casting film - stretching in the direction of the fluid casting film and stretching in the width direction - in the width direction Stretching, stretching in the direction of the fluid casting film, stretching in the direction of the fluid casting film

In addition, simultaneous biaxial stretching also involves stretching in one direction and allowing the other to relax and contract. The preferable stretching ratio of the simultaneous biaxial stretching can be set in the range of ×1.01 times to 1.5 times in the width direction and the length direction.

The amount of residual solvent of the film at the time of stretching is preferably in the range of 20 to 100% by mass at the start of tentering, and it is preferred to carry out drying while stretching until the amount of residual solvent of the film becomes 10 The mass% or less is more preferably 5% by mass or less.

The drying temperature at the time of stretching is preferably in the range of 30 to 160 ° C, more preferably in the range of 50 to 150 ° C, and most preferably in the range of 70 to 140 ° C.

In the tentering step, the temperature distribution of the ambient gas in the width direction is small, and it is preferable from the viewpoint of improving the uniformity of the film, and the temperature distribution in the width direction in the tentering step is preferably ±5 ° C. Within the range of ± 2 ° C, preferably within ± 1 ° C.

(6) Winding step

When the amount of the residual solvent in the film is 2% by mass or less, the film is taken up as a film by a coiler, and when the amount of the residual solvent is 0.4% by mass or less, a film having good dimensional stability can be obtained. . The special system is wound up in the range of 0.00 to 0.10% by mass.

The winding method can be used by a general user, for example, a fixed torque method, a constant tension method, a tension decay method, a stylized tension control method in which internal stress is constant, and the like, and these methods can be used separately.

The cellulose ester film of the present invention is preferably a long film, specifically a form which exhibits a length of about 100 to 5000 m and is usually provided in a roll shape. Further, the width of the film is preferably in the range of 1.3 to 4 m, and particularly preferably in the range of 1.4 to 3 m.

(Manufacture of cellulose ester film by melt fluid casting method)

The case of producing the cellulose ester film of the present invention by a molten fluid casting method will be described below.

(melted particle manufacturing step)

The resin-containing composition used in melt extrusion is usually preferably kneaded in advance to form granules.

The granulation can be supplied to the extruder by a generally known method such as an additive composed of a dried thermoplastic resin and a heat shrinkable material by a feeder, and using a uniaxial or biaxial extruder. Kneading is carried out, and then extruded into a strip shape from a mold, and then subjected to water cooling or air cooling and then cut.

Raw materials that are dried before extrusion are important to prevent decomposition of raw materials. In particular, since the cellulose ester is easily hygroscopic, it is preferably dried in a range of 70 to 140 ° C for 3 hours or more by a dehumidifying hot air dryer or a vacuum dryer to lower the water content to 200 ppm or less, more preferably 100 ppm or less.

The additives may be supplied to the extruder in advance or separately by separate feeders. A small amount of an additive such as an antioxidant is preferably mixed beforehand in order to uniformly mix.

The mixing of the antioxidants may be carried out by solids, or if necessary, the antioxidant may be previously dissolved in a solvent and impregnated with the thermoplastic resin to be mixed, or sprayed and mixed.

A vacuum conical spiral mixer or the like can be dried and mixed at the same time, which is preferable. Further, when the supply portion or the outlet of the mold or the like is in contact with air, it is preferably configured as dehumidified air or an ambient gas such as dehumidified N ₂ gas.

The extruder preferably suppresses the shearing force and granulates in such a manner that the resin is not deteriorated (molecular weight reduction, coloring, colloid formation, etc.), and is processed as much as possible at a low temperature. For example, in the case of a twin-screw extruder, it is preferred to use a deep groove type screw and rotate it in the same direction. From the viewpoint of the uniformity of pinching, it is preferably an engaging type.

The film obtained by the above was used to form a film. Alternatively, the granulation may be carried out, and the feeder directly supplies the powder of the raw material to the extruder and directly forms a film of the film.

<Step of extruding the molten mixture from the mold to the cooling roll>

First, the granules to be produced are extruded by using a uniaxial or biaxial extruder, and the melting temperature Tm at the time of extrusion is set to about 200 to 300 ° C, and filtered by a filter such as a leaf disc type to remove After the impurities, they were co-extruded into a film shape from the T-die, solidified on a cooling roll, and subjected to fluid casting while being pressed against the elastic contact roll.

When it is introduced into the extruder from the hopper, it is preferably carried out in a vacuum or under reduced pressure or in an inert gas atmosphere to prevent oxidative decomposition and the like. Tm is the temperature at the exit portion of the die of the extruder.

When impurities such as damage or a coagulant of a plasticizer adhere to the mold, streaky defects may occur. The defect is called a mold line. In order to reduce the surface defects of the mold line or the like, the piping from the extruder to the mold is preferably configured to minimize the structure of the resin retention portion. The inside of the mold or the lip is preferably used to minimize damage.

The inner surface of the extruder or the mold which is in contact with the molten resin is preferably a material having a reduced surface roughness or a material having a low surface energy, or a surface which is hard to adhere to the molten resin. Specifically, those who have been subjected to hard chrome plating treatment or ceramic spray treatment to a surface roughness of 0.2 S or less may be mentioned.

The chill roll is not particularly limited, and is a high-rigidity metal roll and has a roll having a structure in which a heat medium or a cold medium capable of controlling temperature can be flowed therein, and the size is not limited as long as it is a film which can be cooled and melt-extruded. The full size is sufficient. Usually, the diameter of the cooling roller is about 100 mm to 1 m.

Examples of the surface material of the cooling roll include carbon steel, stainless steel, aluminum, and titanium. Further, in order to improve the surface hardness or to improve the peeling property from the resin, it is preferred to apply hard chrome plating, nickel plating, amorphous chrome plating, or the like, or surface treatment such as ceramic spraying.

The surface roughness of the surface of the cooling roll is preferably 0.1 μm or less, more preferably 0.05 μm or less, in terms of Ra. The smoother the surface of the roll, the smoother the surface of the resulting film. Of course, the surface-treated surface is preferably further ground to have the above surface roughness.

For the elastic roller, Japanese Patent Laid-Open No. Hei 03-124425, Japanese Patent Application Laid-Open No. Hei 08-224772, and Japanese Patent Laid-Open No. Hei 07-100960 Japanese Patent Publication No. Hei. No. Hei. No. Hei. No. Hei. No. Hei. No. Hei. No. Hei. No. Hei. No. Hei. No. Hei. No. Hei. The surface described in the publication is a polyoxyalkylene rubber roll coated with a thin metal sheath.

When the film is peeled off from the chill roll, it is preferred to control the tension to prevent deformation of the film.

The subsequent steps of the above-mentioned release film are the same as the solution fluid casting method described above.

(optical properties)

The cellulose ester film preferably has a total light transmittance of 90% or more, and particularly preferably 93% or more. In addition, the upper limit of the real face is about 99%. The haze value is preferably 2% or less, and particularly preferably 1.5% or less. The total light transmittance and haze value were measured in accordance with JIS K7361 and JIS K7136.

In order to achieve excellent transparency represented by the total light transmittance, an additive or a copolymerization component that absorbs visible light is not introduced, or an impurity in the polymer is removed by high-precision filtration to reduce light diffusion or absorption inside the film. It is effective. Further, reducing the surface roughness of the film contact portion (the cooling roll, the calender roll, the roll, the belt, the coated substrate in the solution film formation, the transfer roll, etc.) at the time of film formation to reduce the surface roughness of the film surface, or It is also effective by reducing the refractive index of a resin or an additive or the like to reduce light diffusion or reflection on the surface of the film.

In addition, the in-plane phase difference Ro of the cellulose ester film A is at a temperature In an environment of 23° C. and a relative humidity of 55% RH, it is preferable to be in the range of 0 to 100 nm when measuring at a wavelength of 590 nm.

The phase difference Rt in the thickness direction is not particularly limited, but is preferably in the range of -10 to 100 nm.

Further, preferably, the in-plane retardation value Ro of the cellulose ester film A is in the range of 105 to 160 nm at an optical wavelength of 590 nm in an environment of a temperature of 23 ° C and a relative humidity of 55% RH. The cellulose ester film A was obliquely bonded to the direction of the slow axis of the cellulose ester film A in a direction of 45° ± 10° or 135° ± 10° with respect to the absorption axis of the polarizing plate. By bonding in this configuration, the polarizing plate can be circularly polarized, and the visibility when wearing polarized sunglasses can be greatly improved.

The phase difference Rt in the thickness direction at this time is not particularly limited, but is preferably in the range of 70 to 400 nm.

Ro and Rt are values defined by the following formulas (i) and (ii).

Formula (i): Ro = (n _{x -} n _y ) × d

Formula (ii): Rt = [(n _x + n _y ) / 2 - n _z ] × d (wherein n _x is the refractive index in the direction of the slow axis in the plane of the base film, and n _y is in the base The refractive index in the direction perpendicular to the slow axis of the material film, n _z is the refractive index in the thickness direction of the base film, and d is the thickness (nm) of the base film.

For the measurement of the phase difference described above, for example, KOBRA-21AWR (Oji Scientific Instruments Co., Ltd.) can be used.

The above preferred phase difference can be determined by the type or addition of the aforementioned plasticizer The amount, the film thickness of the film, the stretching conditions, and the like are adjusted, and are particularly imparted by stretching conditions in which the stretching ratio in the width direction is 30% or more.

(hard coating)

The cellulose ester film A of the present invention preferably has a hard coat layer containing an acrylic resin and can improve the adhesion to the adhesive layer. Further, in the case where the cellulose ester film B has a hard coat layer on the surface opposite to the polarizing film, it is preferable from the viewpoint of the adhesion to the adhesive layer.

The hard coat layer is explained below.

<Activating radiation hardening resin>

The hard coat layer of the present invention is preferably composed of, for example, an active energy ray-curable resin. Therefore, the hard coat composition of the present embodiment preferably contains an active energy ray-curable acrylic resin.

The active energy ray-curable type refers to a resin which is cured by a crosslinking energy reaction or the like by ultraviolet light or electron beam-like activation energy ray irradiation, and is specifically a resin having an ethylenically unsaturated group. More specifically, an ultraviolet curable urethane urethane resin, an ultraviolet curable polyester acrylate resin, an ultraviolet curable acrylate epoxy resin, and an ultraviolet curable acrylic polyol ester resin can be preferably used. Or an ultraviolet curing epoxy resin. Among them, an ultraviolet curable acrylate resin is preferred.

The ultraviolet curable acrylate resin is preferably a polyfunctional acrylate. The polyfunctional acrylate, preferably selected from the group consisting of polyfunctional acrylates A group consisting of a tetraol ester, a polyfunctional pentaerythritol acrylate, a polyfunctional pentaerythritol methacrylate, and a polyfunctional pentaerythritol methacrylate. Here, the polyfunctional acrylate is a compound having two or more acryloxy groups or methacryloxy groups in the molecule.

Examples of the polyfunctional acrylate monomer include ethylene glycol diacrylate, diethylene glycol diacrylate, 1,6-hexanediol diacrylate, neopentyl glycol diacrylate, and triacrylate. Hydroxymethylpropane ester, trimethylolethane triacrylate, tetramethylol methane methane trimethacrylate, tetramethylol methane methane tetramethacrylate, pentaglyceryl triacrylate, neopentyl glycol diacrylate, triacrylic acid Neopentyl glycol ester, neopentyl glycol tetraacrylate, glyceryl triacrylate, dipivalaerythritol triacrylate, dineopentaerythritol tetraacrylate, dineopentaerythritol pentaacrylate, hexaacrylate Pentaerythritol ester, tris(propyleneoxyoxyethyl) isocyanate, ethylene glycol dimethacrylate, diethylene glycol diethylene glycol ester, 1,6-hexyl dimethacrylate Glycol ester, neopentyl glycol dimethacrylate, trimethylolpropane trimethacrylate, trimethylolethane trimethacrylate, tetramethylol methane trimethacrylate, tetramethyl Tetramethylolmethacrylate, pentaglyceryl trimethacrylate, dimethacrylate Pentaerythritol ester, neopentyl glycol trimethacrylate, neopentyl glycol tetramethacrylate, glyceryl trimethacrylate, dineopentaerythritol trimethacrylate, two new tetramethyl methacrylate Pentaerythritol ester, dineopentaerythritol pentamethyl acrylate, dineopentaerythritol hexamethacrylate, activated energy ray hardening type trimeric isocyanate derivative, and the like. Commercially available products of these polyfunctional acrylates are available, and it is possible to obtain neopentyl glycol tris/tetraacrylate (manufactured by Shin-Nakamura Chemical Co., Ltd., A-TMM-3L). Etc.), neopentyl glycol triacrylate (manufactured by Kyoeisha Chemical Co., Ltd., PE-3A). These compounds may be used alone or in combination of two or more.

The trimeric isocyanate derivative of the active energy ray-curable resin is not particularly limited as long as it has a structure in which one or more ethylenically unsaturated groups are bonded to the isocyanuric acid skeleton. It is preferably a compound having three or more ethylenically unsaturated groups and one or more trimeric isocyanate rings in the same molecule.

A commercially available product can also be used as the trimeric isocyanate compound, and, for example, A-9300 manufactured by Shin-Nakamura Chemical Co., Ltd., and the like can be used. A commercially available product of a trimeric isocyanate compound is, for example, Aronix M-125 manufactured by Toagosei Co., Ltd., and the like. A mixture of a trimeric isocyanate compound and a trimeric isocyanate compound may, for example, be Aronix M-315, Aronix M-313, or the like manufactured by Toagosei Co., Ltd. The activated energy ray-curable trimeric isocyanate derivative modified by ε-caprolactone may, for example, be a trimeric isocyanuric acid tris-(propenyloxyethyl) ester modified with ε-caprolactone. A-9300-1CL manufactured by Shin-Nakamura Chemical Co., Ltd., Aronix M-327 manufactured by Toagosei Co., Ltd., etc., but is not limited thereto.

Further, a monofunctional acrylate can also be used as the active energy ray-curable resin. Examples of the monofunctional acrylate include isodecyl acrylate, 2-hydroxy-3-phenoxypropyl acrylate, isostearyl acrylate, benzyl acrylate, ethyl carbitol acrylate, phenoxyethyl acrylate, Dodecyl acrylate, isooctyl acrylate, tetrahydrofurfuryl acrylate, behenyl acrylate, 4-hydroxybutyl acrylate, 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, cyclohexyl acrylate, and the like. A monofunctional acrylate can be obtained from Shin-Nakamura Chemical Industry Co., Ltd. or Osaka Organic Chemical Industry Co., Ltd. These compounds may be used alone or in combination of two or more. Further, it may be an oligomer of a dimer or a trimer of the above monomer.

Further, as the active energy ray-curable resin, ethyl urethane acrylate may also be used. For example, commercially available products such as Beamset 575CB manufactured by Arakawa Chemical Industries Co., Ltd. and UA-306H manufactured by Kyoei Chemical Co., Ltd. can be used.

The viscosity of the above polyfunctional acrylate is preferably 3,000 mPa ‧ or less, more preferably 1,500 mPa ‧ s or less at 25 ° C. Very good is below 1000mPa‧s. Examples of the low viscosity resin include glyceryl triacrylate, neopentyl glycol triacrylate, and neopentyl glycol tetraacrylate. The aforementioned viscosity is a value measured using an E-type viscometer at 25 °C.

The amount of the above-mentioned active energy ray-curable resin in the hard coat composition is usually in the range of 10 to 99 parts by mass, preferably in the range of 35 to 99 parts by mass, based on 100 parts by mass of the entire composition. . When the amount of the active energy ray-curable resin is small, it is difficult to sufficiently obtain the film strength of the hard coat layer. Further, when the amount is too large, when it is applied by a coating method generally known to be described later, problems such as uniformity of film thickness or occurrence of coating streaks are easily impaired, which is not preferable.

<Cationic Polymerizable Compound>

The hard coat layer may further contain a cationically polymerizable compound, and the cationically polymerizable compound may be used as long as it is cationically polymerized by irradiation of an active energy ray or heat to form a resin. Specific examples thereof include an epoxy group, a cyclic ether group, a cyclic acetal group, a cyclic lactone group, a cyclic thioether group, a helical orthoester compound, and an ethylene side oxy group. Among them, a compound having a functional group such as an epoxy group or a vinyl ether group can be preferably used in the present invention. Examples of the cationically polymerizable compound having an epoxy group or a vinyl ether group include phenyl glycidyl ether, ethylene glycol diglycidyl ether, glycerol diglycidyl ether, ethylene oxide cyclohexene, and lemon dioxide oil. 3,4-epoxycyclohexylmethyl-3',4'-epoxycyclohexanecarboxylate, bis-(6-methyl-3,4-epoxycyclohexyl) adipate, 2 -(3,4-epoxycyclohexyl)ethyltrimethoxy decane, diethylene glycol divinyl ether, polyethylene glycol divinyl ether, 1,4-cyclohexane dimethanol divinyl ether, and the like. Further, a polymer compound can also be used as the epoxide.

When the cationically polymerizable compound is contained in the hard coat layer composition, the amount of the cationically polymerizable compound in the hard coat layer composition is usually in the range of 1 to 90 parts by mass based on 100 parts by mass of the entire composition. Preferably, it is in the range of 1 to 50 parts by mass.

<microparticle>

The hard coat layer may further contain fine particles. Examples of the fine particles include inorganic fine particles and organic fine particles. Examples of the inorganic fine particles include cerium oxide, titanium oxide, aluminum oxide, tin oxide, indium oxide, ITO, zinc oxide, zirconium oxide, magnesium oxide, calcium carbonate, calcium carbonate, talc, clay, sintered kaolin, and sintered tannin. Calcium, hydrated calcium citrate, aluminum citrate, magnesium citrate and calcium phosphate. Examples of the organic fine particles include polymethyl methacrylate acrylate resin powder, acryl styrene resin powder, polymethyl methacrylate resin powder, oxime resin powder, polystyrene resin powder, and polycarbonate resin. Powder, benzoguanamine resin powder, melamine resin powder, polyolefin resin powder, polyester resin powder, polyamine resin powder, polyimine resin powder, or polyvinyl fluoride resin powder Wait. The average particle diameter of these fine particles is preferably in the range of 30 to 200 nm from the viewpoint of stability or clarity of the hard coat coating composition. Further, the hard coat layer may contain two or more kinds of fine particles having different particle diameters.

<Other additives, method for producing hard coat layer>

In the hard coat layer, in order to promote the hardening of the above-mentioned active energy ray-curable resin, it is preferred to further contain a photopolymerization initiator. The blending amount of the photopolymerization initiator is preferably contained in a mass ratio of a photopolymerization initiator: an active energy ray-curable resin = 20:100 to 0.01:100.

Specific examples of the photopolymerization initiator include alkylphenones, acetophenones, diphenylketones, hydroxydiphenylketones, Michelin, α-amyl esters, thioxanthone, and the like. Derivatives, but are not limited thereto. As such a commercially available product, for example, Irgacure 184, Irgacure 907, Irgacure 651 manufactured by BASF Japan Co., Ltd., and the like are exemplified as preferred examples.

Further, the hard coat layer may contain the same ultraviolet absorber as the above ultraviolet absorber.

Further, the hard coat layer may constitute two or more layers. When two or more hard coat layers are provided, the film thickness of the hard coat layer in contact with the cellulose ester film is preferably in the range of 0.05 to 2 μm. Two or more layers of lamination can be formed by lamination at the same time. The simultaneous lamination means that two or more hard coat layers are applied to the cellulose ester film in a wet-on-wet manner without a drying step to form a hard coat layer. When the second hard coat layer is laminated on the first hard coat layer in a wet-stacking manner without a drying step, it may be laminated one by one by an extrusion coater or by having a plurality of slits. The slit mold is laminated at the same time.

Further, as a method of producing a hard coat layer, a hard coat coating composition is prepared by swelling a cellulose ester film or dissolving a part of a solvent, and the hard coat coating composition is coated by the following method. The method of drying and hardening the cellulose ester film is preferable from the viewpoint of easily obtaining the adhesion between the hard coat layer and the cellulose ester film.

A solvent which swells or dissolves a part of the cellulose ester film is preferably a solvent containing a ketone and/or an acetate. Specifically, examples of the ketone include methyl ethyl ketone, acetone, and cyclohexanone. Further, examples of the acetate include ethyl acetate, methyl acetate, and butyl acetate. The hard coat coating composition may contain an alcohol solvent as another solvent.

The coating amount of the hard coat coating composition is preferably in the range of 0.1 to 40 μm, more preferably in the range of 0.5 to 30 μm, in terms of the film thickness of the film. Further, the dry film thickness is an average film thickness of about 5 to 20 μm, preferably in the range of 7 to 12 μm.

Hard coating, gravure coating, dip coating, reverse coating, wire A generally known coating method such as bar coating, compression molding (extrusion) coating, or inkjet method, coating a hard coat coating composition for forming a hard coat layer, drying and irradiating after coating The active energy ray (also referred to as UV hardening treatment) can be formed by heat treatment after UV curing as necessary. The heat treatment temperature after the UV curing is preferably 80 ° C or higher, more preferably 100 ° C or higher, and particularly preferably 120 ° C or higher. The heat treatment after UV curing at such a high temperature can further improve the mechanical strength (friction resistance, pencil hardness) of the hard coat layer.

In order to impart anti-glare property to the hard coat layer, it is preferred to carry out the drying temperature in the deceleration drying zone by high-temperature treatment at 80 ° C or higher. More preferably, the temperature in the deceleration drying zone is 95 ° C or more and 130 ° C or less. By setting the temperature in the deceleration drying zone to a high temperature treatment, convection can be generated in the coating resin at the time of formation of the hard coat layer, and as a result, fine surface roughness can be easily exhibited on the surface of the hard coat layer, and it is easy to obtain The arithmetic mean roughness Ra value to be described later is preferable from this viewpoint.

In general, the drying process is known as a state in which the drying speed changes from a certain state to a gradually decreasing state when drying starts, and a section in which the drying speed is constant is called a constant-rate drying section, and the drying speed is reduced. The interval is called the deceleration drying section. In the constant rate drying section, the inflowing heat consumes solvent evaporation on the surface of the coating film. When the solvent on the surface of the coating film decreases, the evaporation surface moves from the surface to the inside and enters the deceleration drying section. Thereafter, as the surface temperature of the coating film rises, the temperature is higher, so that the temperature of the ultraviolet curable resin composition rises, and the viscosity of the resin is lowered to increase the fluidity.

The light source for the UV hardening treatment can be used without limitation as long as it is a light source capable of generating ultraviolet rays. For example, a low pressure mercury lamp, a medium pressure mercury lamp, a high pressure mercury lamp, an ultra high pressure mercury lamp, a carbon arc lamp, a metal halide lamp, a xenon lamp, or the like can be used.

The irradiation conditions vary depending on various lamps, and the amount of activation energy rays to be irradiated is usually in the range of 50 to 1000 mJ/cm ² , preferably in the range of 50 to 300 mJ/cm ² .

Further, when the active energy ray is irradiated, it is preferred to carry out the tension to the transport direction of the film, and it is more preferable to apply the tension to the width direction. The tension imparted is usually in the range of 30 to 500 N/m, preferably in the range of 30 to 300 N/m. The method of imparting the tension is not particularly limited, and the tension may be applied to the back roller to the conveyance direction, or the tension may be applied to the width direction or the biaxial direction by a tenter. Thereby, a film having better planarity can be obtained.

The hard coat layer may contain a conductive agent for imparting antistatic property, and a preferred conductive agent may be a metal oxide particle or a π-conjugated conductive polymer. Further, an ionic liquid can also be preferably used as the conductive compound.

The fluoro-nonane graft polymer refers to a copolymer obtained by grafting at least a polyoxyalkylene and/or an organic polyoxyalkylene containing a siloxane and/or an organic siloxane. The polymer of the substance. Commercially available products include ZX-022H, ZX-007C, ZX-049, and ZX-047-D manufactured by Fuji Chemical Industry Co., Ltd.

The polyoxyalkylene-based surfactant is a surfactant in which a part of a methyl group of a polysiloxane oil is substituted with a hydrophilic group. Hydrophilic group Ether, polyglycerol, pyrrolidone, trimethylglycine, sulfate, phosphate, quaternary salt, and the like. Specific examples of the polyoxyalkylene surfactants include SH200, BY16-873, PRX413 (dimethylpolysiloxane oil; manufactured by Toray Dow Corning Silicone Co., Ltd.), SH203, SH230, and SF8416 (alkane). Base modified polyoxyalkylene oil; manufactured by Toray Dow Corning Silicone Co., Ltd., SF8417, BY16-208, BY16-209, BY16-849, BY16-872, FZ-2222, FZ-2207 (dimethyl poly a siloxane-polyethylene oxide linear block copolymer; FZ series manufactured by Nippon Unicar Co., Ltd.), KF-101, KF-102, KF-105 (epoxy modified polyoxyalkylene oxide) Oil; manufactured by Shin-Etsu Chemical Co., Ltd.), BYK-UV3500, BYK-UV3510, BYK-333, BYK-331, BYK-337 (polyether modified polyether oil; BYK Japan), etc. It is not limited to this.

Further, these components are preferably added in a range of 0.01 to 5% by mass based on the solid content in the coating liquid.

(surface shape of hard coating)

The hard coat surface of the present invention preferably has an arithmetic mean roughness Ra of 4 to 20 nm from the viewpoint of an anti-caking effect when wound in a long film form and a good adhesion to a cellulose ester film or an adhesive layer. The scope.

The arithmetic mean roughness Ra is a value measured by an optical interference type surface roughness meter (RST/PLUS, manufactured by WYKO Co., Ltd.) according to JIS B 0601:1994.

Further, the unevenness average interval Sm is preferably in the range of 3 to 40 μm. Further, the ratio (Ra/Sm) of the arithmetic mean roughness Ra of the hard coat layer to the uneven pitch Sm of the hard coat coating setting surface of the cellulose ester film is preferably 2 × 10 ^-4 to 6 × A range of 10 ^-3 .

Sm is the same as the arithmetic mean roughness Ra, and can be measured by an optical interference type surface roughness meter (RST/PLUS, manufactured by WYKO Co., Ltd.) in accordance with JIS B 0601:1994.

In order to set the arithmetic mean roughness Ra within the above range, a method of pressing the mold to form a protrusion on the surface, or a method of mixing a resin having a different SP value (solubility parameter) to form a surface unevenness may be used, or by A method of forming a protrusion by phase decomposition or nucleation.

The mold roll used for the formation of the protrusions may be suitably selected such that the unevenness is fine to the thick and uneven, and the pattern may be arranged in a regular or irregular manner, and the pattern may be arranged in a rough pattern, a cylindrical shape, or a spherical shape. .

Further, the haze value of the hard coat film of the present invention is preferably from 1% or less in terms of clarity, and sufficient brightness and high contrast can be obtained.

<functional layer>

The cellulose ester film A and the cellulose ester film B of the present invention may be provided with a functional layer such as a back coat layer, an antireflection layer, or an antiglare layer in addition to the hard coat layer.

(back coating)

On the side of the cellulose ester film of the present invention which is provided with the hard coat layer On the reverse side, a back coating to prevent warping or agglomeration may be provided.

From the viewpoint of preventing warpage or agglomeration, cerium oxide, titanium dioxide, aluminum oxide, zirconium oxide, calcium carbonate, calcium carbonate, talc, clay, sintered kaolin, sintered calcium citrate, and oxidation may be added to the back coat layer. Particles such as tin, indium oxide, zinc oxide, ITO, hydrated calcium citrate, aluminum citrate, magnesium citrate and calcium phosphate.

The particles contained in the back coat layer are preferably in the range of 0.1 to 50% by mass based on the binder. The increase in haze at the time of providing the back coat layer is preferably 0.5% or less, and particularly preferably 0.1% or less. The binder is preferably a cellulose ester resin. Further, in the coating composition for forming the back coat layer, a solvent containing an alcohol, a ketone, and/or an acetate saccharide is preferred.

(anti-reflection layer)

In the cellulose ester film of the present invention, the antireflection layer may be applied to the upper layer of the hard coat layer to be used as an antireflection film having an external light reflection preventing function.

The antireflection layer is preferably laminated by considering the refractive index, the film thickness, the number of layers, the layer order, and the like in a manner of reducing the reflectance by optical interference. The antireflection layer is preferably a low refractive index layer having a lower refractive index than a protective film as a support, or a combination of a high refractive index layer and a low refractive index layer having a higher refractive index than a protective film as a support. Composition. Particularly preferred is an antireflection layer composed of three or more refractive index layers. It is preferable to use a refractive index layer which is different in refractive index from the support side (the refractive index is higher than the support and the refractive index is higher). Layer with low refractive index layer) / three layers of high refractive index layer / low refractive index layer By. Alternatively, it is preferable to use an antireflection layer in which two or more layers of a high refractive index layer and two or more low refractive index layers are alternately laminated.

The layer constitution of the antireflection layer can be considered as follows, but is not limited thereto.

Cellulose ester film / hard coat / low refractive index layer

Cellulose ester film / hard coat / medium refractive index layer / low refractive index layer

Cellulose ester film / hard coat / medium refractive index layer / high refractive index layer / low refractive index layer

Cellulose ester film/hard coat layer/high refractive index layer (conductive layer)/low refractive index layer

Cellulose ester film / hard coat / anti-glare layer / low refractive index layer

(low refractive index layer)

The low refractive index layer preferably contains ceria-based fine particles, and the refractive index is preferably in the range of 1.30 to 1.45 at 23 ° C and a wavelength of 550 nm.

The film thickness of the low refractive index layer is preferably in the range of 5 nm to 0.5 μm, more preferably in the range of 10 nm to 0.3 μm, and most preferably in the range of 30 nm to 0.2 μm.

The composition for forming a low refractive index layer preferably contains at least one or more particles having an outer shell layer and having a porous or void inside, as the cerium oxide-based fine particles. In particular, particles having a shell layer and having a porous or hollow interior are preferably hollow ceria-based particles.

The composition for forming a low refractive index layer may contain an organic telluride represented by the following general formula (OSi-1) or a hydrolyzate thereof, or the polycondensate.

General formula (OSi-1): Si(OR) ₄

An organic telluride represented by the above general formula, wherein R represents an alkyl group having 1 to 4 carbon atoms. Specifically, tetramethoxysilane, tetraethoxysilane, tetraisopropyloxane or the like can be preferably used.

Other solvents may be added, and a decane coupling agent, a hardener, a surfactant, or the like may be added as necessary. In addition, it may contain thermosetting and/or photocuring, which is mainly composed of a fluorine-containing compound containing a fluorine atom and having a crosslinkable or polymerizable functional group in a range of 35 to 80% by mass. Compound. Specifically, it is a fluorine-containing polymer or a fluorine-containing sol-gel compound. a fluoropolymer, for example, in addition to a hydrolyzate or a dehydrated condensate containing a perfluoroalkyl decane compound [eg, heptafluoro-1,1,2,2-tetrahydroindenyl)triethoxy decane] A fluorine-containing copolymer having a fluorine-containing monomer unit and a crosslinking reactive unit as a constituent unit is exemplified. Other solvents may be added, and a decane coupling agent, a hardener, a surfactant, or the like may be added as necessary.

(high refractive index layer)

When the refractive index of the high refractive index layer is measured at 23 ° C and a wavelength of 550 nm, the refractive index is preferably adjusted in the range of 1.4 to 2.2. Further, the thickness of the high refractive index layer is preferably in the range of 5 nm to 1 μm, more preferably in the range of 10 nm to 0.2 μm, and most preferably in the range of 30 nm to 0.1 μm. The means of adjusting the refractive index can be added by adding metal oxide particles or the like Achieved. The refractive index of the metal oxide or the metal oxide fine particles used is preferably in the range of 1.80 to 2.60, more preferably in the range of 1.85 to 2.50.

The type of the metal oxide fine particles is not particularly limited, and may be selected from the group consisting of Ti, Zr, Sn, Sb, Cu, Fe, Mn, Pb, Cd, As, Cr, Hg, Zn, Al, Mg, Si, P, and A metal oxide of at least one element of S, such metal oxide fine particles may be doped with a trace atom of Al, In, Sn, Sb, Nb, a halogen element, Ta or the like. In addition, a mixture of these may also be used. In the present invention, particularly preferred is the oxidation of at least one metal selected from the group consisting of zirconium oxide, cerium oxide, tin oxide, zinc oxide, indium tin oxide (ITO), antimony-doped tin oxide (ATO), and zinc antimonate. The particles are the main component. The special series contains zinc phthalate particles.

The average particle diameter of the primary particles of the metal oxide fine particles is in the range of 10 to 200 nm, and particularly preferably in the range of 10 to 150 nm. The average particle diameter of the metal oxide fine particles can be measured from an electron microscope photograph taken by a scanning electron microscope (SEM) or the like. It can also be measured by a particle size distribution meter using a dynamic light scattering method or a static light scattering method. When the particle diameter is too small, aggregation tends to occur, and the dispersibility is deteriorated. When the particle size is too large, the haze will rise remarkably, which is not preferable. The shape of the metal oxide fine particles is preferably a rice grain shape, a spherical shape, a cubic shape, a spindle shape, a needle shape or an unshaped shape.

The metal oxide fine particles can be surface-treated by an organic compound. By modifying the surface of the metal oxide fine particles by the organic compound, the dispersion stability in the organic solvent can be improved, the dispersed particle diameter can be easily controlled, and aggregation and sedimentation which occur over time can be suppressed. Therefore, it is better The surface modification quality by the organic compound is preferably in the range of 0.1 to 5% by mass, particularly preferably 0.5 to 3% by mass, based on the metal oxide fine particles. Examples of the organic compound used for the surface treatment include a polyol, an alkanolamine, a stearic acid, a decane coupling agent, and a titanate coupling agent. Among them, a decane coupling agent is preferred. Two or more surface treatments can be combined. Further, the high refractive index layer may also contain a π-conjugated conductive polymer. The π-conjugated conductive polymer can be used as long as it is an organic polymer having a main chain composed of a π-conjugated system. For example, polythiophenes, polypyrroles, polyanilines, polyphenylenes, polyacetylenes, polystyrenes, polyacenes, polythiophenesethylenes, and the like may be mentioned. From the viewpoint of easiness of polymerization and stability, polythiophenes, polyanilines, and polyacetylenes are preferred.

The π-conjugated conductive polymer can obtain sufficient conductivity and solubility to the binder resin even without substitution, but can further introduce an alkyl group, a carboxyl group, or a sulfonic acid group in order to further improve conductivity and solubility. a functional group such as an alkoxy group, a hydroxyl group, a cyano group or the like.

Further, an ionic compound may also be contained. Examples of the ionic compound include an imidazolium-based, pyridinium-based, alicyclic-based amine-based, aliphatic amine-based, aliphatic guanidine-based cation, inorganic ionic system such as BF ₄ ^- or PF ₆ ^- , and CF ₃ SO. a compound composed of a fluorine-based anion such as ₂ ^- or (CF ₃ SO ₂ ) ₂ N ^- or CF ₃ CO ₂ ^- . The ratio of the polymer to the binder is preferably in the range of 10 to 400 parts by mass based on 100 parts by mass of the polymer, and particularly preferably, the binder is located in 100 parts by mass of the polymer. Within the range of 100 to 200 parts by mass.

[Examples]

The invention is specifically described by the following examples, but the invention is not limited thereto. In the examples, the expression "part" or "%" is used, and when it is not specifically stated, it means "parts by mass" or "% by mass".

Example 1 <Production of Touch Panel Module>

The ITO film was formed on the tempered glass so as to have a thickness of 20 nm by sputtering, and the first electrode pattern in the X direction was formed by etching.

Next, SiO _{2 was} formed into a film so as to have a thickness of 200 nm by using a sputtering method as an insulating layer disposed between the electrode patterns, and then the ITO film was formed by sputtering to have a thickness of 20 nm. On the upper side, a second electrode pattern in the Y direction is formed by etching. Next, SiO _{2 was} formed on the upper side by sputtering using a sputtering method so as to have a thickness of 200 nm.

The Ag paste was applied to the electrode patterns of the formed ITO in the X direction and the Y direction, respectively, and sintered, and was connected to the control circuit via the lead wires thus fabricated.

Next, the cellulose ester film A1 produced under the following conditions was bonded to the second electrode pattern through an adhesive layer to fabricate the touch panel module 1.

The adhesive layer is an acrylic adhesive.

<Cellulose ester film>

Hereinafter, the types and contents of the cellulose ester film used in the examples are as follows.

CE-1: Cellulose diacetate (acetamyl substitution degree 2.45, Mw 300,000)

CE-2: Cellulose diacetate (acetamyl substitution degree 2.15, Mw 300,000)

CE-3: Cellulose diacetate (acetamyl substitution degree 2.35, Mw 300,000)

CE-4: Cellulose acetate propionate (acetamyl substitution degree 1.9, propyl ketone substitution degree 0.45, Mw280,000)

CE-5: Cellulose acetate propionate (acetamyl substitution degree 1.9, propyl ketone substitution degree 0.95, Mw290,000)

CE-6: Cellulose triacetate (acetamyl substitution degree 2.88, Mw320,000)

<Production of Cellulose Ester Film A1> <Particle dispersion 1>

The above ingredients were stirred and mixed by a dissolver for 50 minutes, and then dispersed by a Manton-Gaulin homogenizer.

<Particle Addition Liquid 1>

The fine particle dispersion 1 was slowly added while sufficiently stirring the dissolution tank into which methylene chloride was introduced. Then, the dispersion is carried out by an attritor so that the particle diameter of the secondary particles becomes a predetermined size. This was filtered by Finemet NFF manufactured by Nippon Seisen Co., Ltd. to prepare a particulate additive liquid 1.

<Main paint A>

The main paint A of the following composition was prepared. First, dichloromethane and ethanol were placed in a pressurized dissolution tank. Next, the cellulose acetate was placed in a pressurization dissolution tank into which the solvent was introduced while stirring. This was completely dissolved while heating and stirring. The main paint A was prepared by filtering using Angstrom filter paper No. 244 manufactured by Anchip Paper Co., Ltd.

Put the above components into a closed container and stir them to dissolve them. Produce paint. Next, the coating was uniformly fluid-cast on the stainless steel belt support at a temperature of 33 ° C and a width of 1500 mm using an endless steel strip fluid casting apparatus. The temperature of the stainless steel belt is controlled at 30 °C.

On the stainless steel belt support, the amount of residual solvent of the film after evaporating the solvent to the fluid casting film (casting) was 75%, and then peeling off from the stainless steel belt support at a peeling tension of 130 N/m.

While applying heat of 160 ° C to the peeled cellulose ester film, it was stretched by 10% in the width direction using a tenter. The residual solvent at the start of stretching was 15%. The drying is then terminated by transporting the plurality of rolls over the drying zone. The drying temperature was set to 130 ° C, and the conveying tension was set to 100 N/m. After drying, it was cut into a width of 1.5 m, and a knurling process of a width of 10 mm and a height of 10 μm was applied to both ends of the film, and the film was wound into a roll to obtain a cellulose ester film A1 having a dried film thickness of 50 μm. The roll length is 5200m.

The phase difference of the cellulose ester film A1 was measured by the aforementioned measurement method, and as a result, the in-plane retardation value Ro was 20 nm.

<Production of cellulose ester film A2~A7>

The cellulose ester films A2 to A7 were produced in the same manner as the cellulose ester film A1 except that the resin (type, degree of substitution) and film thickness were changed as described in the first table.

<Production of COP film>

As a comparative film, a cycloolefin film (trade name: Zeonor, thickness: 30 μm, manufactured by Zeon Corporation, Japan) was used.

<PC film>

A polycarbonate film (trade name: Pure Ace C110-75, thickness: 75 μm, manufactured by Teijin Kasei Co., Ltd.) was used as a comparative film.

<PET film>

A polyethylene terephthalate film (trade name: PET50T600E, thickness: 50 μm, manufactured by Mitsubishi Plastics Co., Ltd.) having a pressure-sensitive adhesive layer was used as a comparative film.

<Production of polarizing plate> <Production of Cellulose Ester Film B1> <Main paint B>

The above-mentioned components were placed in a sealed container, and the mixture was heated and stirred to be completely dissolved, and the mixture was filtered using Anisoara Paper Co., Ltd., manufactured by Anime Paper Co., Ltd., to prepare a main coating material B.

A steel strip fluid casting device is then used to uniformly cast the film onto the stainless steel strip support. On the stainless steel belt support, the solvent was evaporated until the amount of residual solvent became 100%, and it was peeled off from the stainless steel belt support. The solvent in the film of the cellulose ester film was evaporated at 35 ° C, cut into a width of 1.15 m, and dried at a drying temperature of 160 ° C while being stretched by 15% in the width direction by a tenter. Then, it was conveyed in a drying apparatus at 120 ° C by a plurality of rolls, dried for 15 minutes, cut into 1.5 m width, and subjected to a knurling process of a width of 10 mm and a height of 5 μm at both ends of the film, and coiled at The core was rolled to obtain a cellulose ester film B1. The cellulose ester film B1 had a film thickness of 30 μm and a roll length of 5000 m.

The phase difference of the cellulose ester film B1 was measured by the following measurement method, and as a result, the in-plane retardation value Ro was 5 nm.

Similarly, as described in the first table, the cellulose ester films B2 and B3 were produced by changing only the film thickness.

Next, using the produced cellulose ester film B1, a polarizing plate was produced.

(a) Production of polarizing film

10 parts by mass of glycerin and 170 parts by mass of water are melt-kneaded to 100 parts by mass of polyvinyl alcohol (hereinafter abbreviated as PVA) having a degree of saponification of 99.95 mol% and a degree of polymerization of 2400, and after defoaming, from the T-die The film is formed by melt extrusion on a metal roll. Then, drying and heat treatment are carried out to obtain a PVA film.

The obtained PVA film had an average thickness of 25 μm, a moisture content of 4.4%, and a film width of 3 m. Then sequentially the obtained PVA film is continuous A pre-swelling, dyeing, uniaxial stretching by a wet method, fixing treatment, drying, and heat treatment were carried out to prepare a polarizing film. That is, the PVA film was immersed in water at a temperature of 30 ° C for 30 seconds to carry out preliminary swelling, and then immersed in an aqueous solution having an iodine concentration of 0.4 g / liter and a potassium iodide concentration of 40 g / liter at a temperature of 35 ° C for 3 minutes. Then, in a 50% aqueous solution having a boric acid concentration of 4%, a uniaxial stretching of 6 times, a potassium iodide concentration of 40 g/liter, a boric acid concentration of 40 g/liter, and chlorination under conditions of a tensile force of 700 N/m applied to the film. The zinc concentration was 10 g/liter in an aqueous solution at 30 ° C for 5 minutes to carry out a fixing treatment. Then, the PVA film was taken out, dried by hot air at a temperature of 40 ° C, and then heat-treated at a temperature of 100 ° C for 5 minutes. The obtained polarizing film had an average thickness of 13 μm, and the polarizing property was 43.0%, the degree of polarization was 99.5%, and the dichroic ratio was 40.1.

(b) Production of polarizing plate

Following the following steps 1 to 4, the cellulose ester film B1 was bonded to both surfaces of the polarizing film to prepare a polarizing plate.

Step 1: The polarizing film was immersed in a storage tank of a 2% by mass solid content polyvinyl alcohol cement solution for 1 to 2 seconds.

Step 2: The cellulose ester film B1 was subjected to alkali treatment under the following conditions. Next, in step 1, the polarizing film is immersed in a polyvinyl alcohol adhesive solution. The excess adhesive adhering to the immersed polarizing film was gently removed, and the polarizing film was sandwiched from both sides by the cellulose ester film B1, and laminated, and a roll-shaped polarizing plate was produced.

(alkali treatment)

After the saponification treatment, water washing, neutralization, and water washing were sequentially carried out, followed by drying at 100 °C.

Step 3: The laminate was bonded at a rate of about 2 m/min by a pressure of 20 to 30 N/cm ² by two rotating rolls. At this point, care must be taken not to allow air bubbles to enter.

Step 4: The sample prepared in the step 3 was dried in a dryer at a temperature of 100 ° C for 5 minutes to prepare a roll-shaped polarizing plate.

Similarly, as described in the first table, the cellulose ester films B2 and B3, and the COP film, the PC film, and the PET film were used to produce a polarizing plate.

<Production of Liquid Crystal Display Panel>

In the liquid crystal display panel, the touch panel module and the polarizing plate attached to the liquid crystal cell are carefully and carefully peeled off from a commercially available liquid crystal display device with a touch panel.

Next, the polarizing plate produced above was bonded to the liquid crystal cell through an adhesive layer containing an acrylic adhesive to prepare a liquid crystal display panel.

Coating on the surface of the cellulose ester film A1 of the touch panel module SVR1240 manufactured by Sony Chemical and Information Device.

Next, the coated SVR 1240 is bonded to the cellulose ester film B1 of the liquid crystal display panel, and a part of the ultraviolet rays are irradiated to be temporarily fixed. After checking whether bubbles are generated on the interface, the ultraviolet ray is irradiated to the entire surface to completely harden the touch panel module and the liquid crystal display panel, and the liquid crystal display device 1 with the touch panel is produced.

Similarly, a liquid crystal display device 2 to 10 with a touch panel was produced by using a combination of the cellulose ester film of the first table and a COP film, a PC film, and a PET film.

<Measurement of water absorption and moisture permeability of film>

The water absorption rate of the film was determined according to JIS K 7209-1984 (water absorption rate of plastic and boiling water absorption test method), and water absorption (%) of each film converted to a thickness of 40 μm was obtained.

The moisture permeability of the film was measured by the moisture permeability of each film converted to a thickness of 40 μm in accordance with JIS Z0208. The unit is g/m ² /24 hr (40 ° C, 90% RH test).

<Evaluation of liquid crystal display device with touch panel> (1) Durable peelability

The liquid crystal display device with the touch panel produced was subjected to 200 cycles of one cycle at a temperature of -20 ° C to 80 ° C at intervals of 30 minutes in an environment of a relative humidity of 50% RH. Visually The change of the adhesion of the adhesive layer between the touch panel module of the liquid crystal display device and the liquid crystal display panel is observed.

○: no change

△: The edge only produces a little peeling

×: peeling occurs outside the edge

(2) Warpage of the display panel

After the liquid crystal display device with the touch panel was continuously lit for 100 hours at 60 ° C and 90%, the amount of warpage of the display panel at this time was confirmed. The amount of warpage is to place the display device on a flat platform and determine the height of the panel warp being the largest part of the platform.

○: The amount of warpage at the end is less than 1 mm.

△: The amount of warpage at the end is 1 to 1.5 mm or less.

×: The amount of warpage at the end exceeds 1.5 mm.

(3) Anti-dispersion

After attaching the cellulose ester film A to a glass plate having a length of 150 mm × a width of 170 mm × a thickness of 1 mm, on a platform having a height of 10 mm, the cellulose ester film A is directed upward (the direction opposite to the above-mentioned stage) and A laminate of the glass plate and the cellulose ester film A was placed at a height of 30 cm so that a portion (one end portion) of one end in the longitudinal direction of the laminate was floated in an arch shape. The iron ball having a diameter of 31.75 mm was dropped to the one end portion, and the scattering state of the glass was visually observed.

The film is not cracked as ○, and the film is cracked as ×.

From the contents of the first table, the liquid crystal display device with the touch panel using the cellulose ester film A and the cellulose ester film B of the present invention can be known, compared with the COP film, the PC film, and the PET of the comparative example. In the film, the adhesive layer C between the touch panel module and the liquid crystal display panel is not peeled off, and the warpage of the panel and the scattering resistance of the glass are also good.

The thickness of the cellulose ester film B was set to be thicker than the thickness of the cellulose ester film A (No. 3), and the warpage amount of the panel was only slightly increased.

Example 2 <Coating setting of hard coat layer>

The following hard coat composition 1 was filtered by a polypropylene filter having a pore diameter of 0.4 μm using an extrusion coater, and applied to the above-prepared cellulose ester films A1 to A6 at a temperature of 80 ° C. After the drying, the nitrogen gas was purged so that the oxygen concentration became 1.0% by volume or less, and the coating was performed at an irradiation amount of 0.25 J/cm ² at an illuminance of 100 mW/cm ² in the irradiation portion using an ultraviolet lamp. The layer was hardened to form a hard coat layer 1 having a dry film thickness of 3 μm and wound up to produce a roll-shaped hard coat film A1H to A6H.

<hard coating composition 1>

The following materials were stirred and mixed to constitute a hard coat composition 1.

Tris/tetrabutyl pentoxide (NK Ester A-TMM-3L, manufactured by Shin-Nakamura Chemical Co., Ltd.) 50 parts by mass

A touch panel module was produced in the same manner as in the first embodiment using the hard-coated films A1H to A6H, and the touch panel module was bonded to the liquid crystal display panel via the SVR 1240.

The liquid crystal display device with the touch panel of the hard-coated film A1H~A6H to be assembled is placed at a relative humidity of 90% RH at intervals of 30 minutes, from -20 ° C to 80 ° C. The forced deterioration cycle test was carried out by performing 300 cycles in a cycle. The liquid crystal display devices 1 to 6 with the touch panel produced in Example 1 were slightly warped on the panel, but the hard coat film A1H to A6H was used. With the liquid crystal display device with a touch panel, peeling and warpage were not observed at all.

Example 3

In the production of the cellulose ester film A1, a cellulose ester film C1 was produced in the same manner except that the film was stretched by 45% in the width direction by a tenter.

The phase difference of the cellulose ester film C1 was measured by the following measurement method, and as a result, the in-plane phase difference value Ro was 145 nm.

(evaluation of retardation film) (direction of the slow phase axis)

The Abbe refractometer (1T) was used to measure the average refractive index of the sample in the environment at a temperature of 23 ° C and a relative humidity of 55% RH at a wavelength of 590 nm, and to obtain a slow phase axis. direction.

(phase difference: measurement of retardation)

The in-plane phase difference value Ro is obtained by the following equation.

Formula (i): Ro = (n _{x -} n _y ) × d (nm)

Here, d is a thickness (nm) of the film, a refractive index n _x (refractive index in the direction of the slow axis), and a refractive index n _y (refractive index in a direction perpendicular to the slow axis in the film plane).

The above-mentioned retardation value Ro was measured using an automatic complex refractive index meter KOBRA-21AWR (Oji Scientific Instruments Co., Ltd.).

By using the cellulose ester film C1 produced, the slow axis of the cellulose ester film C1 is inclined to 45° with respect to the absorption axis of the polarizing plate of the liquid crystal display panel. A liquid crystal display device with a touch panel was produced in the same manner as in the first embodiment of the touch panel module.

When the liquid crystal display unit is worn by the polarized sunglasses, the liquid crystal display device 1 with the touch panel produced in the first embodiment has a part of the image, but the touch panel is made in the embodiment. The liquid crystal display device has no invisible image, and it is known that the visibility is good.

Industrial applicability:

The liquid crystal display device with a touch panel of the present invention has a scattering prevention function against cracking of the glass substrate, and does not cause peeling of the bonding portion between the touch panel module and the liquid crystal display panel or warpage of the panel Therefore, it can be widely applied as a liquid crystal display device with a touch panel.

1‧‧‧ glass substrate

2‧‧‧1st electrode pattern

3‧‧‧Insulation

4‧‧‧2nd electrode pattern

5‧‧‧Adhesive layer

6‧‧‧Cellulose ester film A

7‧‧‧hard coating

T‧‧‧Touch Panel Module

8‧‧‧Adhesive layer C

9‧‧‧Cellulose ester film B

10‧‧‧ polarizing film

11‧‧‧Protective film

P‧‧‧Polar plate

12‧‧‧LCD panel

V‧‧‧Liquid Display Department

Claims (6)

A liquid crystal display device with a touch panel, comprising a touch panel module and a liquid crystal display device with a touch panel of the liquid crystal display panel, wherein: (1) the touch panel module has a square shape a transparent conductive film formed on the outermost glass substrate, and having a cellulose ester film A having a thickness in the range of 15 to 60 μm on the transparent conductive film, (2) the liquid crystal display panel having a cellulose ester on the outermost surface The film B and (3) the cellulose ester film A and the cellulose ester film B are bonded to each other via the adhesive layer C. The liquid crystal display device with a touch panel according to the first aspect of the invention, wherein the thickness of the cellulose ester film B is in the range of 10 to 40 μm. The liquid crystal display device with a touch panel according to claim 1 or 2, wherein the cellulose ester film A has a hard coat layer containing an acrylic resin on a side contacting the liquid crystal display panel. The liquid crystal display device with a touch panel according to the first aspect of the invention, wherein the cellulose ester film A is a cellulose diacetate having a degree of substitution of an oxime group in the range of 2.0 to 2.5. The liquid crystal display device with a touch panel according to claim 1, wherein the in-plane phase difference Ro of the cellulose ester film A is in an environment of a temperature of 23 ° C and a relative humidity of 55% RH at a wavelength of 590 nm. The measurement is in the range of 0 to 100 nm. The liquid crystal display device with a touch panel according to claim 1, wherein the in-plane phase difference Ro of the cellulose ester film A is in an environment of a temperature of 23 ° C and a relative humidity of 55% RH at a wavelength of 590 nm. In the measurement, it is in the range of 105 to 160 nm, and the retardation axis of the cellulose ester film A is in the direction of 45°±10° or 135°±10° with respect to the absorption axis of the polarizing plate. In this manner, the cellulose ester film A is inclined and bonded.